On the order of kinetics in the study of thermoluminescence

The definition of first-order, second-order and other possible kinetics in thermoluminescence are discussed in relation to a recent paper by Hagekyriakou and Fleming (1982). The definitions offered for 'first-order kinetics' include 'classical' and 'pseudo'-first-order kinetics, all of which have the same properties and therefore are usually indistinguishable. Second-order kinetics are defined in a quite restrictive manner which leaves many intermediate cases which are neither of first nor of second order. The properties of the different kinetics in thermoluminescence peaks are compared as well as the kinetic order tests. The conclusions given by Hagekyriakou and Fleming are examined critically, and somewhat different conclusions are reached.