SPIN-ORBIT TRANSITIONS (P-2(1 2)[-P-2(3/2)) OF IODINE AND BROMINE ATOMS IN SOLID RARE-GASES/

Infrared absorptions of iodine and bromine atoms in solid rare-gases a re presented. The isolated atoms are produced by UV-photolysis of HI o r HBr in solid Ar, Kr and Xe. The absorptions are characterised by sha rp zero-phonon lines and broad structured phonon side bands. Some of t he zero-phonon lines are resolved and split into two components, separ ated by a few wavenumbers. The production of the atoms follow second-o rder kinetics indicating that the primary hydrogen atom undergoes a se condary reaction with the hydro en halide producing a halogen atom and a hydrogen molecule. This is supported by the observation of the infr ared absorptions of hydrogen molecules in concentrated matrices after photolysis. (C) 1998 Elsevier Science B.V.