Determination of the quadrupole moment tensor of ethylene by collision-induced absorption

Abstract

The collision-induced rotation-translation spectrum of gaseous ethylene has been measured at 295 K over the density range 3.7–23.9 amagat in the 40–360 cm −1 frequency region, and at densities up to 50 amagat at 2.3 cm −1 and at 29.6 cm −1. Comparison of two spectral moments of the observed spectrum with the theoretical spectral moments yields values for the two independent (Σ α Q αα = 0) molecular principal quadrupole components Q xx = −4.00, Q yy = 2.02, Q zz = 1.98 × 10 −26 esu.