Ab initio calculations of the static and dynamic polarizability of BaOH

Abstract

We present ab initio calculations of the static and dynamic electric dipole polarizability of the barium monohydroxide (BaOH) molecule, using relativistic coupled-cluster theory. By thoroughly investigating the dependence of the calculated polarizabilities on computational parameters (basis set size, treatment of relativistic and QED effects, level of description of electron correlation, and vibrational corrections), a procedure for determining uncertainties is constructed and applied. The electric dipole moment of BaOH is also calculated and compared to experiment. The static and dynamic (for λ = 1064 nm) polarizability tensor elements were calculated within the electronic ground state for both the (000) vibrational ground state and the (010) bending vibrationally excited state, the latter state being particularly interesting for a wide range of quantum experiments. The ground-state static polarizability tensor elements are calculated to be 200.8(24) a.u. and 297(5) a.u. for the parallel and perpendicular components, respectively.