Stretching and bending dynamics in triatomic ultralong-range Rydberg molecules

TL;DR

This paper explores the structure and vibrational dynamics of triatomic ultralong-range Rydberg molecules, revealing how kinetic couplings influence their linear configurations through advanced computational methods.

Contribution

It introduces a computational approach using the Rydberg electron Green's function to efficiently analyze triatomic Rydberg molecules and uncovers the impact of kinetic couplings on molecular geometry.

Findings

Kinetic couplings induce linear structures in triatomic Rydberg molecules.

The method reduces computational effort for electronic structure calculations.

Vibrational modes are separated into bending and stretching for detailed analysis.

Abstract

We investigate polyatomic ultralong-range Rydberg molecules consisting of three ground state atoms bound to a Rydberg atom via $s$- and $p$-wave interactions. By employing the finite basis set representation of the unperturbed Rydberg electron Green's function we reduce the computational effort to solve the electronic problem substantially. This method is subsequently applied to determine the potential energy surfaces of triatomic systems in electronic $s$- and $p$-Rydberg states. Their molecular geometry and resulting vibrational structure are analyzed within an adiabatic approach that separates the vibrational bending and stretching dynamics. This procedure yields information on the radial and angular arrangement of the nuclei and indicates in particular that kinetic couplings between bending and stretching modes induce a linear structure in triatomic $l=0$ ultralong-range Rydberg molecules.