Molecular Zeeman effect, electric dipole moment, and boron nuclear hyperfine coupling constants in HBS

Abstract

The zero-field microwave spectra of the J =0 → J = 1 transitions in H11B32S, D11B32S, and D10B32S have been observed under high resolution to give the boron nuclear quadrupole coupling constants of eqQ = −3.72±0.03 MHz for 11B and eqQ = −7.91±0.03 MHz for 10B and the nuclear magnetic spin rotation constants along the axis perpendicular to the internuclear axis of M⊥=−7.2 ± 3.0 kHz for 11B and 1M⊥=−2.6 ± 1.0 kHz for 10B. The magnitude of the electric dipole moment was measured by high electric fields (Stark effect) to give |μ| = 1.298 ± 0.005 D. High magnetic fields (Zeeman effect) were used to measure the molecular g values and magnetic susceptibility anisotropies. The results are g⊥=−0.0414 ± 0.0002 and χ⊥−χ∥=7.2 ± 0.5 × 10−6 erg/G2· mole for H11B32S and g⊥=−0.0356 ± 0.0002 and χ⊥−χ∥=9.8 ± 2.1 × 10−6 erg/G2· mole for D11B32S. The resultant molecular electric quadrupole moment is Q∥ =2.7±0.6 × 10−26 esu · cm2 and the g values from the H11B32S–D11B32S isotopic pair were used to determine the sign of the electric dipole moment, + HBS −.