Preferred Label : reaction coordinate;
IUPAC definition : A geometric parameter that changes during the conversion of one (or more) reactant
molecular entities into one (or more) product molecular entities and whose value can
be taken for a measure of the progress of an elementary reaction (for example, a bond
length or bond angle or a combination of bond lengths and/or bond angles; it is sometimes
approximated by a non-geometric parameter, such as the bond order of some specified
bond). In the formalism of 'transition-state theory', the reaction coordinate is that
coordinate in a set of curvilinear coordinates obtained from the conventional ones
for the reactants which, for each reaction step, leads smoothly from the configuration
of the reactants through that of the transition state to the configuration of the
products. The reaction coordinate is typically chosen to follow the path along the
gradient (path of shallowest ascent/deepest descent) of potential energy from reactants
to products. The term has also been used interchangeably with the term transition
coordinate, applicable to the coordinate in the immediate vicinity of the potential
energy maximum. Being more specific, the name transition coordinate is to be preferred
in that context.;
Origin ID : R05168;
See also
A geometric parameter that changes during the conversion of one (or more) reactant
molecular entities into one (or more) product molecular entities and whose value can
be taken for a measure of the progress of an elementary reaction (for example, a bond
length or bond angle or a combination of bond lengths and/or bond angles; it is sometimes
approximated by a non-geometric parameter, such as the bond order of some specified
bond). In the formalism of 'transition-state theory', the reaction coordinate is that
coordinate in a set of curvilinear coordinates obtained from the conventional ones
for the reactants which, for each reaction step, leads smoothly from the configuration
of the reactants through that of the transition state to the configuration of the
products. The reaction coordinate is typically chosen to follow the path along the
gradient (path of shallowest ascent/deepest descent) of potential energy from reactants
to products. The term has also been used interchangeably with the term transition
coordinate, applicable to the coordinate in the immediate vicinity of the potential
energy maximum. Being more specific, the name transition coordinate is to be preferred
in that context.
