On the energy dependence of the Zeeman and hyperfine parameters in the state of OH and OD

Abstract

Abstract We report quantum beat studies of the energy dependence of the Zeeman parameters in the A 2 Σ + state of OH and OD, and the nuclear hyperfine parameters of OD( A 2 Σ + ). In contrast to previous work, we find that the sign and magnitude of the anisotropic g-factor gl for υ′=0 is consistent with that expected from Curl’s relationship. However, at higher energies gl changes sign, a result we attribute to interaction with the repulsive 1 4 Π state, which is known to lead to predissociation at higher energies. The magnetic and electric quadrupole hyperfine constants were determined for OD( A 2 Σ + ,υ ′ =0–3) , and the constants for υ′=2,3 are reported here for the first time. The derived values are consistent with previous experimental results and available ab initio calculations.