Calculation of the local environment of a barium monofluoride molecule in a neon matrix

ABSTRACT

The local environment of a barium monofluoride (BaF) molecule embedded in a neon matrix is studied theoretically. The energy of the BaF-Ne triatomic system is calculated with a scalar relativistic Hamiltonian, using coupled-cluster theory at the CCSD(T) level for 1625 positions of the Ne atom relative to the BaF molecule. The calculations are repeated with increasing basis sets (from double to quintuple zeta), and are extrapolated to estimate the complete-basis-set limit. Using the potential obtained from these calculations, it is determined that substituting a BaF molecule for ten Ne atoms is favoured compared to substitutions for other numbers of Ne atoms. The equilibrium position and orientation of the BaF molecule and the displacement of its nearby Ne neighbours are determined. The potential barriers that prevent the BaF molecule from migrating and rotating are calculated. These barriers are essential for the EDM${}^3$ collaboration, which is using BaF molecules embedded in a noble-gas solid to perform a precision measurement of the electron electric dipole moment.

GRAPHICAL ABSTRACT

KEYWORDS:

• Matrix isolation
• barium monofluoride
• neon

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work is supported by the Alfred P. Sloan Foundation, the Gordon and Betty Moore Foundation, the John Templeton Foundation in conjunction with the Northwestern Center for Fundamental Physics, the Natural Sciences and Engineering Research Council of Canada and York University. Computations for this work were supported by Compute Ontario and the Digital Research Alliance of Canada.