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arXiv · 2609.00306

Use of Cholesky decomposition in the CFOUR program package

Jürgen Gauss·Simon Blaschke·Sophia Burger·Davide Cianchino·Marios-Petros Kitsaras·Luca Melega·Tommaso Nottoli·Jeremias Oswald·Tereza Uhlířová·Chaoqun Zhang·Lan Cheng·Stella Stopkowicz·Filippo Lipparini
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Abstract

An overview is given about our efforts to speed up high-level computations of molec- ular energies and properties using Cholesky decomposition (CD). We describe the cor- responding developments in the CFOUR quantum-chemical package with a focus on (a) the use of CD in complete-active space self-consistent-field (CASSCF) and coupled- cluster (CC) computations, (b) the implementation of analytic CC gradients using CD, (c) the efficient calculation of magnetic properties (NMR shieldings and magnetizabili- ties) using CD when carried out with explicit magnetic-field dependent basis functions, i.e., the so-called gauge-including atomic orbitals (GIAOs), (d) the efficient computa- tion of CASSCF response properties using CD, (e) the use of CD in relativistic two- and four-component computations, as well as (f) computations for molecules in finite magnetic fields using GIAOs together with CD. An outlook on future developments concerning the CFOUR package is given.

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Jürgen Gauss, Simon Blaschke, Sophia Burger, Davide Cianchino, Marios-Petros Kitsaras, Luca Melega, Tommaso Nottoli, Jeremias Oswald, Tereza Uhlířová, Chaoqun Zhang, Lan Cheng, Stella Stopkowicz, Filippo Lipparini. 2026-08-31. Use of Cholesky decomposition in the CFOUR program package. https://arxiv.org/abs/2609.00306

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