The Effect of Nuclear-Quadrupole Coupling in the Laser-Induced Alignment of Molecules

J Phys Chem A. 2020 Mar 19;124(11):2225-2230. doi: 10.1021/acs.jpca.9b11433. Epub 2020 Mar 9.

Abstract

We present a theoretical study of the time-dependent laser alignment of molecules taking into account the hyperfine coupling due to nuclear-quadrupole interactions. The coupling of nuclear spins to the overall angular momentum of molecules significantly influences their rotational dynamics. Here, we systematically analyze the impact of the nuclear-quadrupole coupling on the rotational dynamics of the linear and the asymmetric-top diiodobenzene molecule induced by external laser fields. We explore different regimes of pulse shapes and laser-pulse intensities and detail under which conditions the quadrupole coupling cannot be neglected in the description of the laser alignment of molecules.