PHOTON-ECHO IN MOLECULAR GASES .2. INVESTIGATION OF COLLISIONAL RELAXATION

This paper presents a review of investigations of collisional relaxati on in SF6, HCOF, and (NH3)-N-15 molecular gases and in mixtures of the se gases with buffer gases by means of the photon echo, stimulated pho ton echo, and photon echo in standing waves. We consider the relaxatio n of level populations and the induced dipole moment, analyze the cont ribution of phase-interrupting collisions to homogeneous line broadeni ng, and study the manifestations of elastic scattering by small angles . We discuss the results of investigation devoted to the collisional r elaxation of low-order polarization moments (depolarizing collisions) and examine the possibility of extracting the data concerning the stee pness of interaction potentials in gases from the dependence of the ra te of collisional relaxation on the velocity of translational motion.