Ab initio calculations of the static and dynamic polarizability of BaOH

We present ab initio calculations of the static and dynamic electric dipole polarizability of the bariummonohydroxide (138BaOH) molecule, using relativistic coupled-cluster theory. By thoroughly investigating thedependence of the calculated polarizabilities on computational parameters (basis set size, treatment of relativisticand QED effects, level of description of electron correlation, and vibrational corrections), a procedure fordetermining uncertainties is constructed and applied. The electric dipole moment of BaOH is also calculatedand compared to experiment. The static and dynamic (for λ= 1064 nm) polarizability tensor elements werecalculated within the electronic ground state for both the (000) vibrational ground state and the (010) bendingvibrationally 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 theparallel and perpendicular components, respectively.