2020/03/31 by Marcin Gronowski, Adam M. Koza, Michał Tomza · 30 citations
Chemistry · Physics and Astronomy · #Ab initio #Advanced Chemical Physics Studies #Cold Atom Physics and Bose-Einstein Condensates #Molecular Spectroscopy and Structure #Physics #cond-mat.quant-gas #physics.atom-ph #physics.chem-ph #quant-ph
paper · pdf · doi:10.1103/physreva.102.020801
published in Physical Review A 102(2) (American Physical Society) · 7 pages, 2 figures, 2 tables
openalex created_date 2020/04/03 · openalex publication_date 2020/08/10 · arxiv created 2021/02/14 · arxiv updated 2021/02/16 · openalex updated_date 2026/08/05
Ultracold polar and magnetic 23Na6Li molecules in the rovibrational ground state of the lowest triplet a3\mathrm\ensuremathΣ+ electronic state have been recently produced. Here, we calculate the electronic and rovibrational structure of these 14-electron molecules with spectroscopic accuracy (<0.5\phantom\rule4pt0excm^\ensuremath-1) using state-of-the-art ab initio methods of quantum chemistry. We employ the hierarchy of the coupled-cluster wave functions and Gaussian basis sets extrapolated to the complete basis set limit. We show that the inclusion of higher-level excitations, core-electron correlation, relativistic, QED, and adiabatic corrections is necessary to accurately reproduce scattering and spectroscopic properties of alkali-metal systems. We obtain the well depth, De=229.9(5)\phantom\rule4pt0excm^\ensuremath-1, the dissociation energy, D0=208.2(5)\phantom\rule4pt0excm^\ensuremath-1, and the scattering length, as=\ensuremath-84_\ensuremath-41+25\phantom\rule4pt0exbohr, in good agreement with recent experimental measurements. We predict the permanent electric dipole moment in the rovibrational ground state, d0=0.167(1) D. These values are obtained without any adjustment to experimental data, showing that quantum chemistry methods are capable of predicting scattering properties of many-electron systems, provided relatively weak interaction and small reduced mass of the system.