Calculation of Stark resonance parameters for valence orbitals of the water molecule

TL;DR

This paper applies an exterior complex scaling method to calculate Stark resonance parameters for water molecule orbitals, analyzing how these parameters vary with electric field strength across different ionization regimes.

Contribution

It introduces a computational approach combining exterior complex scaling with finite-element methods for molecular Stark resonance calculations.

Findings

Resonance positions and widths are computed for various electric field strengths.

The method effectively covers tunneling and over-barrier ionization regimes.

Results provide detailed Stark resonance parameters for water molecule orbitals.

Abstract

An exterior complex scaling technique is applied to compute Stark resonance parameters for two molecular orbitals ($1b_{1}$ and $1b_{2}$) represented in the field-free limit in a single-center expansion. For electric DC field configurations that guarantee azimuthal symmetry of the solution the calculation is carried out by solving a two-dimensional partial differential equation in spherical polar coordinates using a finite-element method. The resonance positions and widths as a function of electric field strengths are shown for field strengths starting in the tunnelling ionization regime, and extending well into the over-barrier ionization region.