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arXiv · 2404.01460

Efficient configuration-interaction models for photoionization of molecular dimers

Julio C Ruivo·Thomas Meltzer·Alex G Harvey·Jakub Benda·Zdeněk Mašín
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Abstract

We present R-matrix calculations of photoionization of molecular monomers and dimers, focusing on ammonia (NH3) and formic acid (HCOOH), utilizing configuration-interaction models including the Occupation-Restricted Multiple Active Space (ORMAS) approach. We show that ORMAS is a highly efficient choice for calculating photoionization observables, yielding results that are in excellent agreement with those obtained using the much more demanding configuration-interaction method, Complete Active Space (CAS). We demonstrate that models incorporating single and double (SD) excitations with respect to the Hartree-Fock configuration provide good agreement with experimental data. The approach developed here can be readily applied to study photoionization in complex molecular systems.

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Julio C Ruivo, Thomas Meltzer, Alex G Harvey, Jakub Benda, Zdeněk Mašín. 2024-04-01. Efficient configuration-interaction models for photoionization of molecular dimers. https://arxiv.org/abs/2404.01460

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