Polarised laser fluorescence of Se2. Part 2.—Reorientation of zero nuclear spin homonuclear diatomics

Abstract

The origins of the resistance to change of m-states in translation–rotation energy transfer are further investigated by considering the possibility that coupling of rotational angular momentum to nuclear spin may confer stability. This study reports a polarised-fluorescence investigation of the zero nuclear spin molecule ⁸⁰Se₂ where we find negligible reorientation by elastic collisions and slow reorientation by inelastic processes. This is in line with our previous findings on I₂, Li₂ and NaK but is at variance with the somewhat analogous case of oriented ²P_1/2 atoms.