Long range forces between polar alkali diatoms aligned by external electric fields

TL;DR

This paper calculates long-range electrostatic, induction, and dispersion interactions between polar alkali diatoms aligned by external electric fields, providing detailed theoretical data and analytic solutions for their intermolecular potentials.

Contribution

It introduces comprehensive calculations of long-range interactions and electrostatic moments for polar alkali diatoms under external electric fields, including new analytic solutions.

Findings

Calculated long-range coefficients up to R^{-8}

Provided electrostatic moments and polarizabilities up to octopole order

Derived analytic solutions for low-field electrostatic interactions

Abstract

Long range electrostatic, induction and dispersion coefficients including terms of order $R^{-8}$ have been calculated by the sum over states method using time dependent density functional theory. We also computed electrostatic moments and static polarizabilities of the individual diatoms up to the octopole order using coupled cluster and density functional theory. The laboratory-frame transformed electrostatic moments and van der Waals coefficients corresponding to the alignment of the diatomic molecules were found. We use this transformation to obtain the coupling induced by an external DC electric field, and present values for all XY combinations of like polar alkali diatomic molecules with atoms from Li to Cs. Analytic solutions to the dressed-state laboratory-frame electrostatic moments and long range intermolecular potentials are also given for the DC low-field limit.