text: The general form of the Eyring–Polanyi equation somewhat resembles the Arrhenius equation:
  where  is the rate constant,  is the Gibbs energy of activation,  is the transmission coefficient,  is the Boltzmann constant,  is the temperature, and  is the Planck constant.
  The transmission coefficient  is often assumed to be equal to one as it reflects what fraction of the flux through the transition state proceeds to the product without recrossing the transition state. So, a transmission coefficient equal to one means that the fundamental no-recrossing assumption of transition state theory holds perfectly. However,  is typically not one because (i) the reaction coordinate chosen for the process at hand is usually not perfect and (ii) many barrier-crossing processes are somewhat or even strongly diffusive in nature. For example, the transmission coefficient of methane hopping in a gas hydrate from one site to an adjacent empty site is between 0.25 and 0.5. Typically, reactive flux correlation function (RFCF) simulations are performed in order to explicitly calculate  from the resulting plateau in the RFCF. This approach is also referred to as the Bennett-Chandler approach, which yields a dynamical correction to the standard transition state theory-based rate constant.
  It can be rewritten as:
  One can put this equation in the following form:
  where:
  *  = reaction rate constant
  *  = absolute temperature
  *  = enthalpy of activation
  *  = gas constant
  *  = transmission coefficient
  *  = Boltzmann constant = R/N, N = Avogadro constant
  *  = Planck constant
  *  = entropy of activation
  If one assumes constant enthalpy of activation, constant entropy of activation, and constant transmission coefficient, this equation can be used as follows: A certain chemical reaction is performed at different temperatures and the reaction rate is determined. The plot of  versus  gives a straight line with slope  from which the enthalpy of activation can be derived and with intercept  from which the entropy of activation is derived.