Asymptotically spin forbidden quasimolecular radiative transitions

Theoretical works on radiative transitions produced in thermal collisions of atoms of groups 2А, 12 of the periodic table with atoms of inert gases in the normal state as well as in nonsymmetrical collisions of inert gas atoms are discussed in the review. Such collisions are accompanied by either the decay or the population of the lower metastable state $^{3}P_{2}$. The discussion has been carried out within the framework of analytical approaches based on the Fermi pseudopotential method and semiempirical method. The results on rate constants, absorption coefficients, radiative lifetimes, spectral profiles have been presented.