SEMICLASSICAL STUDY OF AR-2-ASTERISK((3)SIGMA(-IN-MOLECULES POTENTIAL-ENERGY SURFACE FOR THE AR-3-ASTERISK SYSTEM()(U)) EXCIMERS IN A PURE AR AFTERGLOW BY MEANS OF A DIATOMICS)

A diatomics-in-molecules (DIM) potential energy surface (PES) is const ructed for the excited triatomic system Ar-3. This PES is used for a semiclassical study of the formation and collisional vibrational relax ation of Ar-2 excimers by simulation of the collision process Ar(S-1( 0)) + Ar2((3) Sigma(u)(+)). Evidence is presented for the existence o f relatively long-lived Ar-3 complexes which appear to be destroyed i n a series of collisions with Ar(S-1(0)); upper and lower boundaries a re established for the vibrational relaxation process frequency of Ar- 2.