Effective technique for numerical kinetics calculations in a system of anharmonic oscillators. Application to study of the influence of the isotopic composition of molecules on the properties of a carbon monoxide active medium

A technique is described for numerical analysis of kinetic processes in a system of anharmonic oscillators, based on using implicit numerical integration and replacement of derivatives by means of backward differentiation expressions. A comparison is made with calculations by the Runge–Kutta method, and it is shown that the computer time is reduced by a factor of more than 10 when the backward differentiation method is used. The influence of the natural isotopic composition of carbon monoxide molecules on the gain and lasing properties is investigated and shown to be only slight.