Eur. Phys. J. D (2013) 67: 233
https://doi.org/10.1140/epjd/e2013-40462-1

Regular Article

Analytical study of level crossings in the Stark-Zeeman spectrum of ground state OH

¹ School of Physics and Astronomy, Rochester Institute of Technology, 84 Lomb Memorial Drive, Rochester, 14623 New York, USA
² Department of Physics, Willamette University, 900 State Street, Salem, OR 97301, USA

^a e-mail: mb6154@gmail.com

Received: 31 July 2013
Received in final form: 11 September 2013
Published online: 15 November 2013

Abstract

The ground electronic, vibrational and rotational state of the OH molecule is currently of interest as it can be manipulated by electric and magnetic fields for experimental studies in ultracold chemistry and quantum degeneracy. Based on our recent exact solution of the corresponding effective Stark-Zeeman Hamiltonian, we present an analytical study of the crossings and avoided crossings in the spectrum. These features are relevant to non-adiabatic transitions, conical intersections and Berry phases. Specifically, for an avoided crossing employed in the evaporative cooling of OH, we compare our exact results to those derived earlier from perturbation theory.