Cross section of the transverse relaxation of NH3 colliding with spherical perturbers

Abstract

The cross sections of the transverse relaxation of NH 3 colliding with various spherical perturbers are measured and examined as a function of molecular parameters, such as ionization energy, polarizability, and mass. The observed cross sections show good correlation with these molecular parameters. An empirical formula in the unit of Å 2 , ϭ25.5 ͑␣ 2 M ͒ 1/6 , is obtained, where is the cross section, ␣ is the polarizability of the perturber in the unit of Å 3 , and M is the reduced mass of the colliding molecules in the unit of g/mol. This expression can be used to evaluate the cross sections of collisions between NH 3 and other spherical perturbers.