Part of
can be determined by
disjoint from
inverse of
is a
is reverse of
physico-chemical process ontology
process
A phenomenon by which change takes place in a system. In physiological systems, a process may be chemical, physical or both.
physico-chemical process
chemical reaction
A process involving the interconversion of chemical species.
nuclear transformation
The change of one nuclide into another with a different proton number or nucleon number.
nuclear decay
A spontaneous nuclear transformation.
nuclear disintegration
Nuclear decay involving a splitting into more nuclei or the emission of particles.
electron capture
A nuclear transformation in which the nucleus captures an orbital electron.
beta-decay
Nuclear decay in which a beta particle is emitted or in which orbital electron capture occurs.
nuclear fusion reaction
A reaction between two light nuclei resulting in the production of a nuclear species heavier than either initial nucleus.
nuclear fusion
radiative capture
Capture of a particle by a nucleus followed by immediate emission of gamma radiation.
capture
A process in which an atomic or nuclear system acquires an additional particle.
nuclear transition
For a nucleus a change from one quantized energy state into another or a nuclear transformation.
radioactive decay
Nuclear decay in which particles or electromagnetic radiation are emitted or the nucleus undergoes spontaneous fission or electron capture.
spontaneous fission
fission
Nuclear fission which occurs without the addition of particles or energy to the nucleus.
subatomic process
nuclear fission
The division of a nucleus into two or more parts with masses of equal order of magnitude, usually accompanied by the emission of neutrons, gamma radiation and, rarely, small charged nuclear fragments.
thermal fission
Fission caused by thermal neutrons.
alpha-decay
Radioactive decay in which an alpha particle is emitted.
gamma-decay
gamma emission
internal conversion
internal pair production
electron emission
beta- emission
beta negative emission
beta emission
negative beta decay
positron emission
positive beta decay
beta positive emission
beta+ emission
induced fission
nuclear reaction
A transformation of a nucleus which occurs (i) when another nuclear particle approaches closely enough to be influenced by the mutual attractive nuclear force between them or (ii) when affected by an electromagnetic force of sufficient strength.
excitation
Process causing the transition of a system from one state to another of higher energy.
photoexcitation
The production of an excited state by the absorption of ultraviolet, visible, or infrared radiation.
electron transfer
The transfer of an electron from one molecular entity to another, or between two localized sites in the same molecular entity.
outer-sphere electron transfer
A reaction in which the electron transfer takes place with no or very weak (4-16 kJ/mol) electronic interaction between the reactants in the transition state.
inner-sphere electron transfer
A reaction in which the electron transfer takes place with significant (>20 kJ/mol) electronic interaction between the donor and acceptor centres in the transition state.
photoinduced electron transfer
An electron transfer resulting from an electronic state produced by the resonant interaction of electromagnetic radiation with matter.
photophysical process
Photoexcitation and subsequent events which lead from one to another state of a molecular entity through radiation and radiationless transitions. No chemical change results.
photochemical reaction
A chemical reaction caused by absorption of ultraviolet, visible, or infrared radiation.
photoreaction
photolysis
The cleavage of one or more covalent bonds in a molecular entity resulting from absorption of light.
photoionization
Ionization of any species by photons.
photocatalysis
Catalytic reaction involving light absorption by a catalyst or by a substrate.
photoassisted catalysis
Catalytic reaction involving production of a catalyst by absorption of light.
photoluminescence
Luminescence arising from photoexcitation.
excitation energy transfer
energy transfer
A photophysical process in which an excited state of one molecular entity (the donor) is deactivated to a lower-lying state by transferring energy to a second molecular entity (the acceptor) which is thereby raised to a higher energy state.
radiative energy transfer
Transfer of excitation energy by radiative deactivation of a donor molecular entity and reabsorption of the emitted light by an acceptor molecular entity.
Forster excitation transfer
dipole-dipole excitation transfer
A mechanism of excitation transfer which can occur between molecular entities separated by distances considerably exceeding the sum of their van der Waals radii.
Dexter excitation transfer
electron exchange excitation transfer
Excitation transfer occurring as a result of an electron exchange mechanism. It requires an overlap of the wavefunctions of the energy donor and the energy acceptor.
fluorescence
Luminescence which occurs essentially only during the irradiation of a substance by electromagnetic radiation.
phosphorescence
Luminescence involving change in spin multiplicity.
photoreduction
Reduction reactions induced by light.
atomic fluorescence
A combined process of photon absorption by an atom followed by spontaneous photon emission.
photooxidation
Oxidation reactions induced by light.
electronation
reduction
The complete transfer of one or more electrons to a molecular entity.
de-electronation
oxidation
The complete removal of one or more electrons from a molecular entity.
photooxygenation
The incorporation of molecular oxygen into a molecular entity induced by light.
catalytic reaction
autocatalytic reaction
A chemical reaction in which a product (or a reaction intermediate) also functions as a catalyst.
chain reaction
A reaction in which one or more reactive reaction intermediates are continuously regenerated, usually through a repetitive cycle of elementary steps (the 'propagation step').
electron-transfer induced chain reaction
A sequence of reactions such as shown in equations [1]-[3], leading from A to B: [1] A + e- --> A.- ; [2] A.- --> B.- ; [3] B.- + A --> B + A.- ; an analogous sequence involving radical cations (A.+, B.+) is also observed.
electron-transfer catalysis
elementary reaction
A reaction for which no reaction intermediates have been detected or need to be postulated in order to describe the chemical reaction on a molecular scale.
stepwise reaction
A chemical reaction with at least one reaction intermediate and involving at least two consecutive elementary reactions.
consecutive reactions
composite reaction
A chemical reaction for which the expression for the rate of disappearance of a reactant (or rate of appearance of a product) involves rate constants of more than a single elementary reaction.
reaction step
An elementary reaction, constituting one of the stages of a stepwise reaction in which a reaction intermediate (or, for the first step, the reactants) is converted into the next reaction intermediate (or, for the last step, the products) in the sequence of intermediates between reactants and products.
chain reaction step
chain initiation
A reaction or process generating free radicals (or some other reactive reaction intermediates) which then induce a chain reaction.
initiation
chain branching
When in a chain reaction there is a net increase in the number of chain carriers there is said to be chain branching.
degenerate chain branching
Sometimes chain branching is brought about by an intermediate which has a long lifetime compared with an ordinary free radical. If this intermediate can break down in different ways, only one of which leads to branching, there may be a relatively slow increase in the number of radicals, and there is said to be degenerate chain branching.
chain termination
termination
The steps in a chain reaction in which reactive intermediates are destroyed or rendered inactive, thus ending the chain.
chain propagation
An elementary step in a chain reaction in which one chain carrier is converted into another. The conversion can be a unimolecular reaction or a bimolecular reaction with a reactant molecule.
chain-propagating reaction
propagating reaction
branching chain reaction
A chain reaction which includes a propagation step or steps in which there is an increase in the number of active intermediates.
rate-controlling step
rate-determining step
An elementary reaction the rate constant for which exerts a strong effect - stronger than that of any other rate constant - on the overall rate.
rate-limiting
product-determining step
The step of a stepwise reaction, in which the product distribution is determined. The product-determining step may be identical to, or occur later than, the rate-controlling step on the reaction coordinate.
reaction stage
A set of one or more (possibly experimentally inseparable) reaction steps leading to and/or from a detectable or presumed reaction intermediate.
parallel reactions
simultaneous reactions
Composite reactions, in which processes like A --> Y and B --> Z occur in parallel.
opposing reactions
Composite reactions, occurring in forward and reverse directions: A + B <=> Z.
biomacromolecule-catalysed reaction
enzymatic reaction
enzyme-catalysed reaction
abzymatic reaction
catalytic antibody reaction
deoxyribozymatic reaction
deoxyribozyme-catalysed reaction
nucleic acid-catalysed reaction
ribozymatic reaction
ribozyme-catalysed reaction
protein-catalysed reaction
catalysis
The action of a catalyst.
general acid catalysis
The catalysis of a chemical reaction by a series of Bronsted acids HA (which may include the solvated hydrogen ion). The acids HA are unchanged by the overall reaction.
general base catalysis
The catalysis of a chemical reaction by a series of Bronsted bases (which may include the lyate ion).
specific catalysis
The acceleration of a reaction by a unique catalyst, rather than by a family of related substances.
homogeneous catalysis
Catalysis in which only one phase is involved.
heterogeneous catalysis
Catalysis occurring at or near an interface between phases.
noncatalytic reaction
thermal reaction
A chemical reaction caused by absorption of thermal energy.
thermolysis
The uncatalysed cleavage of one or more covalent bonds resulting from exposure of a compound to a raised temperature, or a process in which such cleavage is an essential part.
transformation
The conversion of a substrate into a particular product, irrespective of reagents or mechanisms involved.
substitution
Transformation of the general type: AX + Y --> AY + X.
addition
cycloaddition
A reaction in which two or more unsaturated molecules (or parts of the same molecule) combine with the formation of a cyclic adduct in which there is a net reduction of the bond multiplicity.
alpha-addition
1/1/addition
A chemical reaction resulting in a single reaction product from two or three reacting chemical species, with formation of two new chemical bonds to the same atom in one of the reactant molecular entities.
elimination
In an elimination two groups (called eliminands) are lost most often from two different centres (1/2/elimination or 1/3/elimination, etc.) with concomitant formation of an unsaturation in the molecule (double bond, triple bond) or formation of a new ring.
alpha-elimination
A transformation of the general type: R-Z(X)(Y)-R' --> R-Z-R' + XY [or X + Y, or X(+) + X(-)]
rearrangement
molecular rearrangement
intramolecular rearrangement
In the intramolecular rearrangement, the atoms and groups that are common to a reactant and a product never separate into independent fragments during the rearrangement stage.
true molecular rearrangement
intermolecular rearrangement
In an intermolecular rearrangement, a migrating group is completely free from the parent molecule and is re-attached to a different position in a subsequent step.
apparent rearrangement
degenerate rearrangement
A molecular rearrangement in which the principal product is indistinguishable (in the absence of isotopic labelling) from the principal reactant.
isomerization
isomerisation
A chemical reaction, the principal product of which is isomeric with the principal reactant.
insertion
A chemical reaction or transformation of the general type: X-Z + Y --> X-Y-Z, in which the connecting atom or group Y replaces the bond joining the parts X and Z of the reactant XZ.
extrusion
A transformation in which an atom or group Y connected to two other atoms or groups X and Z is lost from a molecule, leading to a product in which X is bonded to Z, e.g. X-Y-Z --> X-Z + Y.
cheletropic reaction
A form of cycloaddition across the terminal atoms of a fully conjugated system with formation of two new sigma-bonds to a single atom of the ('monocentric') reagent. There is formal loss of one pi-bond in the substrate and an increase in coordination number of the relevant atom of the reagent.
cheletropic elimination
biochemical reaction
biotransformation reaction
biological transport
biological electron transfer
oxidoreductase reaction
Enzymatic redox reaction.
oxidase reaction
reductase reaction
transferase reaction
hydrolase reaction
lyase reaction
isomerase reaction
ligase reaction
acid anhydride hydrolase reaction
phosphorus-containing anhydride hydrolase reaction
nucleoside-triphosphatase reaction
nucleoside triphosphate phosphohydrolase reaction
NTP + H2O --> NDP + phosphate
nucleoside-triphosphate diphosphatase reaction
NTP + H2O --> NMP + diphosphate
nucleoside-triphosphate diphosphohydrolase reaction
nucleoside triphosphate (di)phosphohydrolase reaction
synthase reaction
X=Y + Z --> X-Y-Z
transmembrane transport
active transport
The carriage of a solute across a biological membrane from low to high concentration which requires the expenditure of (metabolic) energy.
facilitated diffusion
Diffusion across a biological membrane through the participation of specific transporting agents (transporters) or carriers.
simple diffusion
passive diffusion
A diffusion across a membrane in the absence of any specific transporting agent or carrier.
primary active transport
secondary active transport
diphosphate-bond-hydrolysis-driven transport
decarboxylation-driven transport
methyl-transfer-driven transport
oxidoreduction-driven transport
light-driven transport
transmembrane electron transfer
transmembrane electron transport
two-electron transmembrane electron transfer
one-electron transmembrane electron transfer
antiport
countertransport
The process of coupled solute translocation in which two solutes equilibrate across an osmotic barrier, the translocation of solute being coupled to the translocation of the other in the opposite direction.
symport
The process of solute translocation in which two solutes equilibrate across an osmotic barrier, and the translocation of one solute is coupled to the translocation of the other in the same direction.
cotransport
solute transport
group translocation
Any process in which a substance to be transported across a biological membrane undergoes covalent modification prior crossing the membrane.
photobiochemical reaction
intermembrane electron transfer
one-electron transfer
two-electron transfer
solvation
Any stabilizing interaction of a solute (or solute moiety) and the solvent or a similar interaction of solvent with groups of an insoluble material.
coordination
The formation of a covalent bond, the two shared electrons of which have come from only one of the two parts of the molecular entity linked by it, as in the reaction of a Lewis acid and a Lewis base to form a Lewis adduct.
unimolecular heterolysis
The cleavage of a covalent bond so that both bonding electrons remain with one of the two fragments between which the bond is broken (A:B --> A + :B).
colligation
The formation of a covalent bond by the combination or recombination of two radicals (A. + .B -> A:B).
unimolecular homolysis
A unimolecular reaction involving homolysis of a bond (not forming part of a cyclic structure) in a molecular entity containing an even number of (paired) electrons results in the formation of two radicals (A:B --> A. + .B).
homolysis
heterolysis
attachment
A transformation by which one molecular entity (the substrate) is converted into another by the formation of one (and only one) two-centre bond between the substrate and another molecular entity and which involves no other changes in connectivity in the substrate.
detachment
The reverse of an attachment.
association
The assembling of separate molecular entities into any aggregate, especially of oppositely charged free ions into ion pairs or larger and not necessarily well-defined clusters of ions held together by electrostatic attraction.
dissociation
The separation of a molecular entity into two or more molecular entities (or any similar separation within a polyatomic molecular entity).
ionization
The generation of one or more ions. It may occur, e.g. by loss of an electron from a neutral molecular entity, by the unimolecular heterolysis of such an entity into two or more ions, or by a heterolytic substitution reaction involving neutral molecules.
electron attachment
The transfer of an electron to a molecular entity, resulting in a molecular entity of (algebraically) increased negative charge.
electron detachment
The reverse of an electron attachment.
electronic transition
spin-allowed electronic transition
An electronic transition which does not involve a change in the spin part of the wavefunction.
vibronic transition
A transition which involves a change in both the electronic and vibrational quantum numbers of a molecular entity, as opposed to purely electronic or purely vibrational transitions.
charge-transfer transition
CT transition
An electronic transition in which a large fraction of an electronic charge is transferred from one region of a molecular entity, called the electron donor, to another, called the electron acceptor (intramolecular CT) or from one molecular entity to another (intermolecular CT).
pi-sigma* transition
An electronic transition described approximately as a promotion of an electron from a 'bonding' pi orbital to an 'antibonding' sigma orbital designated as sigma*. Such transitions generally involve high transition energies and appear close to or mixed with Rydberg transitions.
pi-->sigma* transition
sigma-sigma* transition
sigma-->sigma* transition
An electronic transition described approximately as promotion of an electron from a 'bonding' sigma orbital to an 'antibonding' sigma orbital designated as sigma*. Such transitions generally involve high transition energies, and appear close to or mixed with Rydberg transitions.
ligand to metal charge transfer transition
LMCT transition
An electronic transition in a metal complex that corresponds to excitation populating an electronic state in which considerable electron transfer from a ligand to a metal centre has occurred.
metal to ligand charge transfer transition
MLCT transition
An electronic transition of a metal complex that corresponds to excitation populating an electronic state in which considerable electron transfer from the metal to a ligand has occurred.
metal to metal charge transfer transition
An electronic transition of a bi- or polynuclear metal complex that corresponds to excitation populating an electronic state in which considerable electron transfer between two metal centres has occurred.
MMCT transition
intervalence charge transfer
Electron transfer (thermal or photoinduced) between two metal sites differing only in oxidation state. Quite often such electron transfer reverses the oxidation states of the sites. The term is frequently extended to the case of metal-to-metal charge transfer between non-equivalent metal centres.
Rydberg transition
An electronic transition described approximately as promotion of an electron from a 'bonding' orbital to a Rydberg orbital.
microscopic process
macroscopic process
unimolecular reaction
A reaction with a molecularity of one.
bimolecular reaction
A reaction with a molecularity of two.
termolecular reaction
A reaction with a molecularity of three.
phase transition
A change in the nature of a phase or in the number of phases as a result of some variation in externally imposed conditions, such as temperature, pressure, activity of a component or a magnetic, electric or stress field.
magnetic transition
A transition between disordered and ordered arrays of atomic magnetic moments.
diffusion
The spreading or scattering of a gaseous or liquid material.
microscopic chemical event
A process that results in the interconversion of molecular entities.
mesomorphic transition
A transition that occurs between a fully-ordered crystalline solid and an isotropic liquid. Mesomorphic transitions can occur (i) from a crystal to a liquid crystal (ii) from a liquid crystal to another liquid crystal and (iii) from a liquid crystal to an isotropic liquid.
polymorphic transition
A reversible transition of a solid crystalline phase at a certain temperature and pressure (the inversion point) to another phase of the same chemical composition with a different crystal structure.
enantiotropic transition
melting
The conversion of a solid to a liquid by the application of heat and/or pressure.
evaporation
The physical process by which a liquid substance is converted to a gas or vapour.
crystallization
The formation of a crystalline solid from a solution, melt vapour or a different solid phase, generally by the lowering of the temperature or by evaporation of a solvent.
sublimation
The direct transition of a solid to a vapour without passing through a liquid phase.
interphase transition
A transition that occurs at boundaries between phases.
precipitation
The sedimentation of a solid material (a precipitate) from a liquid solution in which the material is present in amounts greater than its solubility in the liquid.
nucleation and growth
A process in a phase transition in which nuclei of a new phase are first formed, followed by the propagation of the new phase at a faster rate.
discontinuous precipitation
A diffusional reaction in a multi-component system in which structural and compositional changes occur in regions immediately adjacent to the advancing interface. The parent phase remains unchanged until swept over by the interface; the transition is complete in regions over which the interface has passed.
continuous precipitation
A diffusional reaction in a multi-component system in which atoms are transported to the growing nuclei by diffusion over relatively large distances in the parent phase and during which the mean composition of the parent phase changes continuously towards its equilibrium value.
agglomeration
The formation and growth of aggregates ultimately leading to phase separation by the formation of precipitates of larger than colloidal size.
micellar solubilization
solubilization
In a system formed by a solvent, an association colloid and at least one other component (the solubilizate), the incorporation of this other component into or on the micelles.
absorption
The process of one material (absorbent) being retained by another (absorbate).
sol-gel transition
The transition of a suspension of solid particles in a liquid (sol) to an apparent solid, jelly-like material (gel).
nucleation
The process by which nuclei are formed in solution.
homogeneous nucleation
The condensation of a single chemical compound in solution.
simultaneous nucleation
The simultaneous condensation of more than one compound in solution.
heterogeneous nucleation
The condensation of a compound in solution on a foreign substance.
electrode process
The totality of changes occurring at or near a single electrode during the passage of current.
electrode reaction
For an electrode process at a given potential the current is controlled by the kinetics of a number of steps which include the transport of reactants to and from the interface and the interfacial reaction itself. The latter, which is called the electrode reaction, must always include at least one elementary step in which charge is transferred from one phase to the other, but may also involve purely chemical steps within the interfacial region.
adiabatic electron transfer
Electron transfer process in which the reacting system remains on a single electronic surface in passing from reactants to products.
diabatic electron transfer
Electron transfer process in which the reacting system has to cross over between different electronic surfaces in passing from reactants to products.
adsorption
An increase in the concentration of a dissolved substance at the interface of a condensed and a liquid phase due to the operation of surface forces. Adsorption can also occur at the interface of a condensed and a gaseous phase.
desorption
The converse of adsorption, i.e. the decrease in the amount of adsorbed substance.
desorption (by displacement)
The process in which expulsion of a previously adsorbed component from the interfacial layer is effected by subsequent stronger adsorption of another component.
dissociative adsorption
Adsorption with dissociation into two or more fragments, both or all of which are bound to the surface of the adsorbent.
dissociative chemisorption
associative desorption
reactive adsorption
Reactive adsorption (and its reverse, reactive desorption) resembles dissociative adsorption (and its reverse, associative desorption) but one fragment adds to an adsorbate rather than to a surface site.
reactive desorption
Reverse of reactive adsorption.
associative adsorption
non-dissociative chemisorption
surface process
interface process
physisorption
physical adsorption
Adsorption in which the forces involved are intermolecular forces (van der Waals forces) of the same kind as those responsible for the imperfection of real gases and the condensation vapours, and which do not involve a significant change in the electronic orbital patterns of the species involved.
van der Waals adsorption
chemisorption
Adsorption which results from chemical bond formation (strong interaction) between the adsorbent and the adsorbate in a monolayer on the surface.
chemical adsorption
charge-transfer adsorption
Oxidative or reductive chemisorption where 'reductive' and 'oxidative' refer to electron gain or loss on species in the solid.
multilayer adsorption
Adsorption such that the adsorption space accommodates more than one layer of molecules, and not all adsorbed molecules are in contact with the surface layer of the adsorbent.
diabatic photoreaction
non-adiabatic photoreaction
Within the Born-Oppenheimer approximation, a reaction beginning on one excited state 'potential-energy surface' and ending, as a result of radiationless transition, on another surface, usually that of the ground state.
adiabatic photoreaction
Within the Born-Oppenheimer approximation, a reaction of an excited state species that occurs on a single 'potential-energy surface'.
electrochemical reaction
electrodeposition
The deposition of dissolved or suspended material by an electric field on an electrode.
electro-crystallization
electrocrystallization
micellar catalysis
The acceleration of a chemical reaction in solution by the addition of a surfactant at a concentration higher than its critical micelle concentration so that the reaction can proceed in the environment of surfactant aggregates (micelles).
nucleophilic catalysis
Catalysis by a Lewis base, involving formation of a Lewis adduct as a reaction intermediate.
inhibition
The decrease in rate of reaction brought about by the addition of a substance (inhibitor), by virtue of its effect on the concentration of a reactant, catalyst or reaction intermediate.
mechanism-based inhibition
Irreversible inhibition of an enzyme due to its catalysis of the reaction of an artificial substrate.
suicide inhibition
competitive inhibition
The reduction in rate due to reduction or loss of activity of a catalyst, caused by adsorption of poison which is not greatly preferred to adsorption of reactant.
activation
chemical activation
When some of the energy required for a reaction is provided by a preceding exothermic chemical reaction there is said to be chemical activation.
activation of catalysis
An added substance that increases the rate of a catalysed reaction is known as an activator, and the effect is called activation.
inhibition of catalysis
reversible enzyme inhibition
linear enzyme inhibition
complete inhibition
simple inhibition
mixed inhibition
non-competitive inhibition
uncompetitive inhibition
reversible enzyme activation
essential activation
In essential activation, the free enzyme without activator bound to it has no activity and does not bind substrate.
compulsory activation
specific activation
hyperbolic activation
partial activation
non-essential activation
enzyme inhibition
irreversible enzyme inhibition
modification of reaction
modification of catalysis
competitive enzyme inhibition
modification of enzyme catalysis
enzyme activation
Any process leading to increase of enzymatic activity.
irreversible enzyme activation
zymogen activation
Conversion of inactive precursors (zymogens) into active enzymes by limited proteolysis.
proteolytic activation
enzyme activation by phosphate group transfer
irreversible modification of enzyme catalysis
reversible modification of enzyme catalysis
hyperbolic inhibition
partial inhibition
non-competitive inhibition by protons
reversible inhibition of catalysis
irreversible inhibition of catalysis
catalytic poisoning
The action of catalytic poison.
temporary poisoning
Weak and reversible adsorption of a poison, such that removal of the poison from the fluid phase results in restoration of the original catalytic activity.
polymerization
The process of converting a monomer or a mixture of monomers into a polymer.
condensation polymerization
polycondensation
Polymerization by a repeated condensation process.
condensation reaction
A (usually stepwise) reaction in which two or more reactants (or remote reactive sites within the same molecular entity) yield a single main product with accompanying formation of water or of some other small molecule, e.g. ammonia, ethanol, acetic acid, hydrogen sulfide.
condensation
ring-opening polymerization
A polymerization in which a cyclic monomer yields a monomeric unit which is acyclic or contains fewer cycles than the monomer.
stereoselective polymerization
Polymerization in which a polymer molecule is formed from a mixture of stereoisomeric monomer molecules by incorporation of only one stereoisomeric species.
chain polymerization
A chain reaction in which the growth of a polymer chain proceeds exclusively by reaction(s) between monomer(s) and reactive site(s) on the polymer chain with regeneration of the reactive site(s) at the end of each growth step.
condensative chain polymerization
Chain polymerization occurring with the formation of small molecules.
chain transfer
The abstraction, by the radical end of a growing chain-polymer, of an atom from another molecule. The growth of the polymer chain is thereby terminated but a new radical, capable of chain propagation and polymerization, is simultaneously created.
ionic polymerization
A chain polymerization in which the kinetic-chain carriers are ions or ion pairs.
radical polymerization
A chain polymerization in which the kinetic-chain carriers are radicals.
living polymerization
A chain polymerization from which chain transfer and chain termination are absent.
anionic polymerization
An ionic polymerization in which the kinetic-chain carriers are anions.
cationic polymerization
An ionic polymerization in which the kinetic-chain carriers are cations.
photoinduced polymerization
The polymerization of a monomer by a free radical or ionic chain reaction initiated by photoexcitation.
photoinitiation
The photoproduction of a free radical or ion capable of initiating a chain reaction such as a polymerization.
polyaddition
A polymerization in which the growth of polymer chains proceeds by addition reactions between molecules of all degrees of polymerization.
photopolymerization
Polymerization processes requiring a photon for the propagation step.
cyclopolymerization
A polymerization in which the number of cyclic structures in the constitutional units of the resulting macromolecules is larger than in the monomer molecules.
homopolymerization
Polymerization in which a homopolymer is formed.
copolymerization
Polymerization in which a copolymer is formed.
graft copolymerization
Polymerization in which a graft copolymer is formed.
ring-opening copolymerization
A copolymerization which is a ring-opening polymerization with respect to at least one monomer.
ionic copolymerization
A copolymerization which is an ionic polymerization.
living copolymerization
A copolymerization which is a living polymerization.
radical copolymerization
A copolymerization which is a radical polymerization.
oligomerization
The process of converting a monomer or a mixture of monomers into an oligomer.
telomerization
The formation of an addition oligomer, having uniform end groups X' ... X'', by a chain reaction in which a chain transfer limits the length of the polymer ('telomer') produced.
photoadsorption
Adsorption initiated by light absorbed either by the adsorbate or by the adsorbent. Often it is considered as a chemical step (primary) in a heterogeneous photocatalytic reaction.
photodesorption
Desorption of an adsorbate as a result of exposure to light.
radiocatalysis
Catalysis occurring under the action of quanta of ionizing radiation absorbed by the radiocatalytic substance (radiocatalyst).
radiodesorption
Desorption of a substrate from solid or liquid interfaces induced by absorption of high-energy radiation by the solid or liquid adsorbent.
radioadsorption
Adsorption of a substance at solid or liquid interfaces induced by absorption of high-energy radiation by the solid or liquid adsorbent.
radiothermal catalysis
Radiocatalysis under the action of large radiation fluxes that simultaneously heat the system as a consequence of the absorption of radiation energy.
radiochemical reaction
A chemical reaction caused by absorption of high-energy radiation.
radiolysis
The cleavage of one or several bonds resulting from exposure to high-energynradiation.
autoradiolysis
Radiolysis of a radioactive material resulting directly or indirectly from its radioactive decay.
isomeric transition
A spontaneous transition between two isomeric states of a nucleus.
electron-positron pair production
pair production
The simultaneous formation of an electron and a positron as a result of the interaction of a photon of sufficient energy (> 1.02 MeV) with the field of a particle.
fast atom bombardment ionization
Ionization of any species by causing interaction of the sample (which may be dissolved in a solvent matrix) and a beam of neutral atoms having high translational energy.
luminescence
Spontaneous emission of radiation from an electronically or vibrationally excited species not in thermal equilibrium with its environment.
radioluminescence
Luminescence arising from excitation by high energy particles or radiation.
delayed luminescence
Luminescence decaying more slowly than that expected from the rate of decay of the emitting state.
delayed fluorescence
chemiluminescence
Emission of radiation resulting from a chemical reaction.
electrogenerated chemiluminescence
ECL
electroluminescence
electrochemiluminescence
Luminescence produced by electrode reactions.
triboluminescence
Luminescence resulting from the rubbing together of the surface of certain solids.
sonoluminescence
Luminescence induced by sound waves.
bioluminescence
Luminescence produced by living systems.
thermoluminescence
Luminescence arising from a reaction between species trapped in a rigid matrix and released as a result of an increase in temperature.
piezoluminescence
Luminescence observed when certain solids are subjected to a change in pressure.
deactivation
Any loss of energy by an excited molecular entity.
radiationless deactivation
radiationless decay
non-radiative decay
The loss of electronic excitation energy without photon emission or chemical change.
emission
Radiative deactivation of an excited state; transfer of energy from a molecular entity to an electromagnetic field.
intersystem crossing
An isoenergetic radiationless transition between two electronic states having different multiplicities. It often results in a vibrationally excited molecular entity in the lower electronic state, which then usually deactivates to its lowest vibrational level.
internal conversion (in photophysics)
An isoenenergetic radiationless transition between two electronic states of the same multiplicity. When the transition results in a vibrationally excited molecular entity in the lower electronic state, this usually undergoes deactivation to its lowest vibrational level, provided the final state is not unstable to dissociation.
radiationless transition
A transition between two states of a system without photon emission or absorption.
non-radiative transition
radiative transition
A transition between two states of a molecular entity, the energy difference being emitted or absorbed as photons.
E-type delayed fluorescence
The process in which the first excited singlet state becomes populated by a thermally activated radiationless transition from the first excited triplet state. Since in this case the populations of the singlet and triplet states are in thermal equilibrium, the lifetimes of delayed fluorescence and the concomitant phosphorescence are equal.
P-type delayed fluorescence
The process in which the first excited singlet state is populated by interaction of two molecules in the triplet state (triplet-triplet annihilation) thus producing one molecule in the excited singlet state. In this biphotonic process the lifetime of delayed fluorescence is half the value of the concomitant phosphorescence.
recombination fluorescence
The process in which the first excited singlet state becomes populated by recombination of radical ions with electrons or by recombination of radical ions of opposite charge.
P-type delayed luminescence
Triplet-triplet or singlet-singlet annihilation to form one molecular entity in its excited singlet state and another molecular entity in its electronic ground state.
E-type delayed luminescence
Thermally activated delayed fluorescence involving reversible intersystem crossing.
charge separation
A process in which, under the influence of a suitable driving force (e.g. provided by photoexcitation), electronic charge moves in a direction that increases the difference in local charges between donor and acceptor sites.
charge recombination
Reverse of charge separation.
ion pair dissociation
Separation of the constituents of an ion pair into free ions.
ion-pair return
The recombination of a pair of ions R(+) and Z(-) formed from ionization of RZ.
ion pair return
internal ion-pair return
internal return
If the ions are paired as a tight ion pair and recombine without prior separation into a loose ion pair this is called internal ion-pair return.
external ion-pair return
external return
If the ions are paired as a loose ion pair and form the covalent chemical species via a tight ion pair, this is called external ion-pair return.
geminate recombination
The reaction of two transient species produced from a common precursor in solution with each other.
primary geminate recombination
Geminate recombination occurring before any separation of two transient species by diffusion has occurred.
secondary geminate recombination
If the mutually reactive entities have been separated, and come together by diffusion, this is termed secondary geminate recombination.
singlet-triplet energy transfer
Transfer of excitation from an electronically excited donor in a singlet state to produce an electronically excited acceptor in a triplet state.
excitation annihilation
annihilation
energy pooling
Two atoms or molecular entities both in an excited electronic state interact often (usually upon collision) to produce one atom or molecular entity in an excited electronic state and another in its ground electronic state.
excitation energy annihilation
exciton annihilation
singlet-singlet annihilation
triplet-triplet annihilation
Two atoms or molecular entities both in a triplet state often interact (usually upon collision) to produce one atom or molecular entity in an excited singlet state and another in its ground singlet state. This is often, but not always, followed by delayed fluorescence.
particle-antiparticle pair production
singlet-singlet absorption
Absorption which results in the transition from the singlet ground state of the molecule into singlet excited states and leads to the UV/visible absorption spectrum.
singlet-triplet absorption
Absorption which takes place with the transition from the singlet ground state of the molecule to triplet states and results in the singlet-triplet absorption spectrum.
photoabsorption
absorption (of electromagnetic radiation)
The transfer of energy from an electromagnetic field to an entity (molecular or otherwise).
light absorption
triplet-triplet absorption
Absorption which takes place with the transition from the lowest triplet state of the molecule to higher triplet states thus leading to the triplet-triplet absorption spectrum.
relaxation
If a system is disturbed from its state of equilibrium it relaxes to that state, and the process is referred to as relaxation.
two-photon excitation
Excitation resulting from successive or simultaneous absorption of two photons by an atom or molecular entity.
biphotonic excitation
The simultaneous two-photon absorption.
proton-antiproton pair production
neutron-antineutron pair production
An interaction between a particle and its antiparticle in which they both disappear.
mass transfer
Movement of material from one location in solution to another as might arise either from differences in electrical or chemical potential at the two locations, or from movement of a volume element of solution.
electrophoresis
The motion of colloidal particles in an electric field.
chelatase reaction
ferrochelatase reaction
sirohydrochlorin cobaltochelatase reaction
magnesium chelatase reaction
cobaltochelatase reaction
ATP-hydrolysing chelatase reaction
chemical relaxation
If the equilibrium mixture of a chemical reaction is disturbed by a sudden change, especially of some external parameter (such as temperature, pressure or electrical field strength), the system will readjust itself to a new position of the chemical equilibrium or return to the original position, if the perturbation is temporary. The readjustment is known as chemical relaxation.
vibrational relaxation
The loss of vibrational excitation energy by a molecular entity through energy transfer to the environment caused by collisions. The molecular entity relaxes into vibrational equilibrium with its environment.
resonance fluorescence
Fluorescence from the primary excited atomic or molecular species at the wavelength of the exciting radiation (no relaxation within the excited manifold).
scattering
A process in which a change in direction or energy of an incident radiation is caused by interaction with a particle, a system of particles, or a photon.
light scattering
The redirection of a light beam due to interactions with molecules (Rayleigh and Raman scattering) and aerosols (Mie scattering).
elastic light scattering
Radiation may be scattered by its transmission through a medium containing particles. If the scatter results in no significant change in the wavelength relative to the primary radiation it is called elastic scattering. In cases where the scattering centres are small compared to the wavelength of the radiation the elastic scattering is called Rayleigh scattering and Mie scattering if this condition is not fulfilled.
Rayleigh scattering
The scattering of light by particles and molecules which are much smaller than the wavelength of the light. In the ideal case, the process is one of pure dipole and induced dipole interactions with the electric field of thenlight wave.
Mie scattering
The scattering of electromagnetic radiation by spherical particles of any size r, relative to the wavelength, lambda.
Compton scattering
The elastic scattering of a photon by an electron which afterwards occurs as a free electron. Part of the energy and momentum of the incident photon is transferred to the electron and the remaining part is carried away by the scattered photon.
Compton effect
neutron scattering
electron scattering
elastic electron scattering
inelastic electron scattering
inelastic light scattering
elastic neutron scattering
inelastic neutron scattering
X-ray scattering
elastic X-ray scattering
inelastic X-ray scattering
elastic scattering
inelastic scattering
Raman light scattering
Raman scattering
Brillouin light scattering
Brillouin scattering
endothermic reaction
A reaction for which the overall standard enthalpy change is positive.
exothermic reaction
A reaction for which the overall standard enthalpy change is negative.
exergonic reaction
exoergic reaction
A reaction for which the overall standard Gibbs energy change is negative.
exothermic process
endothermic process
adiabatic process
A process occurring in a thermally insulated system, so that there is no flow of heat to or from the surroundings.
migration
atom migration
The (usually intramolecular) transfer of an atom or group during the course of a molecular rearrangement.
bond migration
The movement of a bond to a new position within the same molecular entity.
migratory insertion
A combination of migration and insertion. The term is mainly used in organometallic chemistry.
postprecipitation
The subsequent precipitation of a chemically different species upon the surface of an initial precipitate usually, but not necessarily, including a common ion.
type I photooxygenation
The reaction of triplet molecular oxygen with radicals formed photochemically.
type II photooxygenation
The reaction of photochemically produced singlet molecular oxygen with molecular entities to give rise to oxygen containing molecular entities.
type III photooxygenation
The photooxygenation reaction proceeding by electron transfer to produce the superoxide radical anion as the reactive species.
photosensitized reaction
A reaction initiated by photosensitization.
photosensitization
The process by which a photochemical change or photophysical process occurs in one (molecular) entity as a result of initial absorption of radiation by anothern(molecular) entity called a photosensitizer. In mechanistic photochemistry, the term is limited to cases in which the photosensitizer is not consumed in the reaction.
photothermocatalysis
Catalysis occurring by the simultaneous or sequential action of light and thermal energy.
thermophotocatalysis
A (photo)catalytic phenomenon that occurs in circumstances when the system is also heated by light.
thermocatalysis
Catalysis occurring by the action of thermal energy.
photoradiocatalysis
Radiocatalysis taking place under the e?ect of the simultaneous action of quanta of light and ionizing radiation. There is also the case when the ionizing radiation alone causes the emission of light that is chemically active (e.g., as may occur in the Cherenkov light emission).
thermochemical reaction
A reaction which involves the enthalpy change.
luciferin monooxygenase reaction
luciferase
Renilla-luciferin 2-monooxygenase reaction
Cypridina-luciferin 2-monooxygenase reaction
Photinus-luciferin 4-monooxygenase (ATP-hydrolysing) reaction
Watasenia-luciferin 2-monooxygenase reaction
Oplophorus-luciferin 2-monooxygenase reaction
Latia-luciferin monooxygenase (demethylating) reaction
alkanal monooxygenase (FMN-linked) reaction
bacterial luciferase
oxygenase reaction
Any oxidoreductase reaction in which dioxygen is the electron acceptor.
dioxygenase reaction
Oxidoreductase reaction involving incorporation of both atoms of dioxygen into the donor.
monooxygenase reaction
Any oxidoreductase reaction that brings about the incorporation of only one atom of oxygen from dioxygen into the donor.
single donor dioxygenase reaction
single donor monooxygenase reaction
internal monooxygenase reaction
paired donor monooxygenase reaction
paired donor dioxygenase reaction
pyrolysis
A chemical degradation reaction that is caused by thermal energy. The term pyrolysis generally refers to an inert environment.
redox reaction
A chemical reaction in which the oxidation of one reactant is coupled to the reduction of a second reactant.
oxidoreduction
oxidation-reduction
ATP diphosphatase reaction
ATP + H2O --> AMP + diphosphate
ATP diphosphohydrolase (diphosphate-forming)
ATPase reaction
ATP + H2O --> ADP + phosphate
ATPase-coupled transmembrane transport
Na+/K+-exchanging ATPase reaction
ATP + H2O + Na+(in) + K+(out) --> ADP + phosphate + Na+(out) + K+(in)
ATP phosphohydrolase (Na+/K+-exchanging)
Na+ export
Na+(in) --> Na+(out)
K+ import
K+(out) --> K+(in)
K+-transporting ATPase reaction
ATP + H2O + K+(out) --> ADP + phosphate + K+(in)
ATP phosphohydrolase (K+-importing)
solvolysis
Generally, reaction with a solvent, or with a lyonium ion or lyate ion, involving the rupture of one or more bonds in the reacting solute. More specifically the term is used for substitution, elimination and fragmentation reactions in which a solvent species is the nucleophile.
hydrolysis
Solvolysis by water.
solvolytic elimination
solvolytic substitution
nucleophilic solvolytic substitution
nucleophilic solvolysis
substitution reaction
A reaction, elementary or stepwise, in which one atom or group in a molecular entity is replaced by another atom or group.
electrophilic substitution reaction
A heterolytic reaction in which the reagent supplying the entering group acts as an electrophile.
nucleophilic substitution reaction
A heterolytic reaction in which the reagent supplying the entering group acts as a nucleophile.
polar reaction
A reaction proceeding by the movement of pairs of electrons from areas of high electron density (nucleophiles) to areas of low electron density (electrophiles), or from filled orbitals to empty orbitals.
homolytic substitution reaction
free-radical substitution
heterolytic substitution reaction
bimolecular nucleophilic substitution
SN2 mechanism
unimolecular nucleophilic substitution
SN1 mechanism
addition reaction
A chemical reaction of two or more reacting molecular entities, resulting in a single reaction product containing all atoms of all components, with formation of two chemical bonds and a net reduction in bond multiplicity in at least one of the reactants.
heterolytic addition reaction
homolytic addition reaction
free-radiacl addition
electrophilic addition
nucleophilic addition
pericyclic addition reaction
simultaneous addition
pericyclic reaction
elimination reaction
oxidative addition
The insertion of a metal of a metal complex into a covalent bond involving formally an overall two-electron loss on one metal or a one-electron loss on each of two metals.
reductive elimination
The reverse of oxidative addition.
unimolecular electrophilic substitution
SE1 mechanism
bimolecular electrophilic substitution
SE2 mechanism
electrocyclic reaction
sigmatropic rearrangement
ene reaction
electrocyclic ring closing
electrocyclic ring opening
The reverse of oxidation.
oxygenation
The incorporation of molecular oxygen into a substrate.
dehydrogenase reaction
dehydrogenation
Oxidation of an organic compound by the removal of one or more hydrogen atoms.
hydrogenation
Reduction of an organic compound by the addition of the hydrogen atoms or dihydrogen.
photohydrogenation
photochemical hydrogenation
photoelectronation
photochemical electronation
solvent transport
osmosis
The spontaneous net flow of solvent by diffusion through a semipermeable membrane from a phase where the solvent has a higher chemical potential to one where the solvent has a lower chemical potential.
electro-osmosis
electro-endosmosis
electrosmosis
The motion of a liquid through a membrane as a consequence of the application of an electric field across the membrane.
membrane process
biological membrane process
biological membrane transport
Any movement of substances or electrons across a biological membrane.
transport
biological membrane fusion
pseudo-catalytic reaction
pseudo-catalysis
Increase the rate of the reaction by one of the reactant that is present in nearly constant concentration but is consumed during the process.
general acid pseudo-catalysis
general base pseudo-catalysis
alkylmercury lyase reaction
alcohol:acceptor dehydrogenase reaction
ethanol:NAD+ dehydrogenase reaction
ethanol dehydrogenase
ethanol + NAD+ --> acetaldehyde + NADH + H+
ethanol dehydrogenation
ethanol --> acetaldehyde + 2 e- + 2 H+
NAD+ reduction
NAD+ + 2 e- + H+ --> NADH
alcohol:NAD(P)+ dehydrogenase reaction
alcohol:NAD+ dehydrogenase reaction
alcohol:NADP+ dehydrogenase reaction
donor:NAD(P)+ oxidoreductase reaction
donor:NAD+ dehydrogenase reaction
donor:NADP+ dehydrogenase reaction
NADP+ reduction
NADP+ + 2 e- + H+ --> NADPH
NAD(P)+ reduction
NAD(P)+ + 2 e- + H+ --> NAD(P)H
methanol:NAD+ dehydrogenase reaction
methanol dehydrogenase
methanol:NAD+ oxidoreductase
methanol + NAD+ --> formaldehyde + NADH + H+
methanol dehydrogenation
methanol --> formaldehyde + 2 e- + 2 H+
aryl-alcohol:NADP+ dehydrogenase reaction
aryl-alcohol dehydrogenase (NADP+)
an aromatic alcohol + NADP+ --> an aromatic aldehyde + NADPH + H+
aryl-alcohol:NADP+ oxidoreductase
propan-2-ol:NADP+ dehydrogenase reaction
isopropanol dehydrogenase (NADP+)
propan-2-ol:NADP+ oxidoreductase
propan-2-ol + NADP+ --> acetone + NADPH + H+
aryl-alcohol:NAD+ dehydrogenase reaction
an aromatic alcohol + NAD+ --> an aromatic aldehyde + NADH + H+
aliphatic alcohol:NAD+ dehydrogenase
an alcohol + NAD+ --> an aldehyde or ketone + NADH + H+
3-hydroxybenzyl-alcohol:NADP+ dehydrogenase reaction
3-hydroxybenzyl-alcohol:NADP+ oxidoreductase
3-hydroxybenzyl-alcohol dehydrogenase
3-hydroxybenzyl alcohol + NADP+ --> 3-hydroxybenzaldehyde + NADPH + H+
3-hydroxybenzyl alcohol dehydrogenation
3-hydroxybenzyl alcohol --> 3-hydroxybenzaldehyde + 2 e- + 2 H+
alcohol dehydrogenation
R-CH(OH)-R' --> R-C(O)-R' + 2 e- + 2 H+
primary alcohol dehydrogenation
R-CH2OH --> R-C(O)H + 2 e- + 2 H+
secondary alcohol dehydrogenation
propan-2-ol dehydrogenation
propan-2-ol --> acetone + 2 e- + 2 H+
aryl-alcohol:NAD(P)+ dehydrogenase reaction
chelation
The formation or presence of bonds between two or more separate binding sites within the same ligand and a single central atom.
donor:hemoprotein oxidoreductase reaction
alcohol:cytochrome dehydrogenase reaction
alcohol:oxygen dehydrogenase reaction
alcohol:quinone dehydrogenase reaction
carbonyl:acceptor dehydrogenase reaction
carbonyl:NAD(P)+ dehydrogenase reaction
carbonyl:cytochrome dehydrogenase reaction
carbonyl:oxygen dehydrogenase reaction
carbonyl:ferredoxin dehydrogenase reaction
donor:iron protein oxidoreductase reaction
donor:iron-sulfur protein oxidoreductase reaction
NAD(P)H:acceptor dehydrogenase reaction
NAD(P)H:NAD(P)+ transhydrogenase reaction
NAD(P)H:hemoprotein dehydrogenase reaction
NAD(P)H:oxygen dehydrogenase reaction
NAD(P)H oxidase reaction
NAD(P)H oxidase
NAD(P)H:oxygen oxidoreductase
NAD(P)H + H+ + O2 --> NAD(P)+ + H2O2
NAD(P)H:quinone dehydrogenase reaction
donor:cytochrome oxidoreductase reaction
donor:oxygen oxidoreductase reaction
donor:quinone oxidoreductase reaction
metal oxidoreductase reaction
metal:NAD(P)+ oxidoreductase reaction
metal:oxygen oxidoreductase reaction
ferroxidase reaction
ferroxidase
Fe(II):oxygen oxidoreductase
metal:flavin oxidoreductase reaction
cob(II)yrinic acid a,c-diamide reductase reaction
cob(II)yrinic acid-a,c-diamide:FMN oxidoreductase
cob(II)yrinic acid a,c-diamide reductase
2 cob(II)yrinic acid a,c-diamide + FMN --> 2 cob(I)yrinic acid a,c-diamide + FMNH2
donor:flavin oxidoreductase reaction
NADPH:mercury oxidoreductase reaction
mercury(II) reductase
Hg2+ + NADPH --> Hg + NADP+ + H+
Hg:NADP+ oxidoreductase
NAD(P)H:metal oxidoreductase reaction
NADPH:cyanocobalamin oxidoreductase reaction
cyanocobalamin reductase (cyanide-eliminating)
cyanocob(III)alamin + NADPH + H+ --> cob(I)alamin + cyanide + NADP+
NADH:diferric-transferrin oxidoreductase reaction
transferrin[Fe(III)]2 + NADH + H+ --> transferrin[Fe(II)]2 + NAD+
NADH:aquacobalamin oxidoreductase reaction
aquacobalamin reductase
2 aquacob(III)alamin + NADH + H+ --> 2 cob(II)alamin + NAD+
NADH:cob(II)alamin oxidoreductase reaction
cob(II)alamin + NADH + H+ --> 2 cob(I)alamin + NAD+
cob(II)alamin reductase
NADPH:aquacobalamin oxidoreductase reaction
2 aquacob(III)alamin + NADPH + H+ --> 2 cob(II)alamin + NADP+
aquacobalamin reductase (NADPH)
NADH:ferric-chelate oxidoreductase reaction
2 Fe(III) + NADH + H+ --> 2 Fe(II) + NAD+
iron chelate reductase
ferric-chelate reductase
NADPH:[methionine synthase] oxidoreductase reaction
2 [methionine synthase]-cob(II)alamin + NADPH + H+ + 2 S-adenosyl-L-methionine --> 2 [methionine synthase]-methylcob(I)alamin + 2 S-adenosylhomocysteine + NADP+
[methionine synthase] reductase
hemoprotein oxidoreductase reaction
hemoprotein:oxygen oxidoreductase reaction
hemoprotein:nitrate oxidoreductase reaction
ferrocytochrome:nitrate reductase reaction
ferrocytochrome:nitrate oxidoreductase
nitrate reductase (cytochrome)
ferrocytochrome + nitrate --> ferricytochrome + nitrite
cytochrome-c oxidase reaction
4 ferrocytochrome c + O2 --> 4 ferricytochrome c + 2 H2O
ferrocytochrome-c:oxygen oxidoreductase
cytochrome-c oxidase
NADPH:metal oxidoreductase reaction
NADH:metal oxidoreductase reaction
hydrogenase reaction
dihydrogenase reaction
hydrogen:NAD(P)+ oxidoreductase reaction
H2 + NAD(P)+ --> H+ + NAD(P)H
hydrogen:NAD+ oxidoreductase reaction
H2 + NAD+ --> H+ + NADH
hydrogen dehydrogenase
hydrogen:NAD+ oxidoreductase
hydrogen:NADP+ oxidoreductase reaction
hydrogen dehydrogenase (NADP+)
hydrogen:NADP+ oxidoreductase
H2 + NADP+ --> H+ + NADPH
hydrogen:cytochrome oxidoreductase reaction
hydrogen:ferricytochrome-c3 oxidoreductase reaction
cytochrome-c3 hydrogenase
H2:ferricytochrome c3 oxidoreductase
2 H2 + ferricytochrome c3 --> 4 H+ + ferrocytochrome c3
hydrogen:quinone oxidoreductase reaction
magnesium-protoporphyrin IX monomethyl ester (oxidative) cyclase reaction
magnesium-protoporphyrin IX 13-monomethyl ester + 3 NADPH + 3 H+ + 3 O2 --> divinylprotochlorophyllide + 3 NADP+ + 5 H2O
hydrogen:ferredoxin oxidoreductase reaction
H2 + oxidized ferredoxin --> reduced ferredoxin + 2 H+
magnesium-protoporphyrin IX 13-monomethyl ester hydroxylase reaction
magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 --> 13(1)-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + NADP+ + H2O
13(1)-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester dehydrogenase reaction
13(1)-hydroxy-magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 --> 13(1)-oxo-magnesium-protoporphyrin IX 13-monomethyl ester + NADP+ + 2 H2O
13(1)-oxo-magnesium-protoporphyrin IX 13-monomethyl ester cyclase reaction
13(1)-oxo-magnesium-protoporphyrin IX 13-monomethyl ester + NADPH + H+ + O2 --> divinylprotochlorophyllide + NADP+ + 2 H2O
tunnelling
The process by which a particle or a set of particles crosses a barrier on its potential-energy surface without having the energy required to surmount this barrier.
quantum tunnelling
quantum tunneling
tunneling
quantum-mechanical tunnelling
proton tunnelling
electron tunnelling
concerted proton tunnelling-electron tunnelling
A concerted process where the proton and the electron tunnel at the same time but independently of each other.
concerted proton tunneling-electron tunneling
PTET
primary photoreaction
Elementary chemical process undergone by an electronically excited molecular entity and yielding a primary photoproduct.
primary photochemical reaction
primary photochemical process
predissociation
Dissociation occurring by tunnelling from a 'bound' to an 'unbound' vibronic state.