Software for the frontiers of quantum chemistry: An overview of developments in the Q-Chem 5 package
- Evgeny Epifanovskyo(Author),
- Andrew T.B. Gilberto, s, cy(Author),
- Xintian Fengo, am, dz(Author),
- Joonho Leeax, dz(Author),
- Yuezhi Maobb, dz(Author),
- Narbe Mardirossiancm, cz, dz(Author)
- ,
- bCornell University,
- cUniversity of Cambridge,
- dHarvard University,
- eVirginia Commonwealth University,
- fUniversity of Nevada Las Vegas
Open access
Abstract
This article summarizes technical advances contained in the fifth major release of the Q-Chem quantum chemistry program package, covering developments since 2015. A comprehensive library of exchange-correlation functionals, along with a suite of correlated many-body methods, continues to be a hallmark of the Q-Chem software. The many-body methods include novel variants of both coupled-cluster and configuration-interaction approaches along with methods based on the algebraic diagrammatic construction and variational reduced density-matrix methods. Methods highlighted in Q-Chem 5 include a suite of tools for modeling core-level spectroscopy, methods for describing metastable resonances, methods for computing vibronic spectra, the nuclear-electronic orbital method, and several different energy decomposition analysis techniques. High-performance capabilities including multithreaded parallelism and support for calculations on graphics processing units are described. Q-Chem boasts a community of well over 100 active academic developers, and the continuing evolution of the software is supported by an "open teamware"model and an increasingly modular design.