The OpenMolcas Web: A Community-Driven Approach to Advancing Computational Chemistry

Abstract

In this article the recent developments of the open-source OpenMolcas chemistry software environment, since spring 2020, are described, with the main focus on novel functionalities that are accessible in the stable branch of the package and/or via interfaces with other packages. These community developments span a wide range of topics in computational chemistry, and are presented in thematic sections associated with electronic structure theory, electronic spectroscopy simulations, analytic gradients and molecular structure optimizations, ab initio molecular dynamics, and other new features. This report represents a useful summary of these developments, and it offers a solid overview of the chemical phenomena and processes that OpenMolcas can address, while showing that OpenMolcas is an attractive platform for state-of-the-art atomistic computer simulations.

Exploiting locality in FCIQMC for fast excitation generation

“…localization), integral evaluations, their transformation to the basis of active molecular orbitals and their storage on the formatted FCIDUMP 34 file were performed using OpenMolcas. 35,36 The new excitation generation has been implemented in a locally modified version of NECI, 3 and will be made publicly available via our open-source repository 37 upon publication of this work.…”