Software for the frontiers of quantum chemistry: An overview of developments in the Q-Chem 5 package
Authors: Epifanovsky Evgeny , Gilbert Andrew T. B. , Feng Xintian , Lee Joonho , Mao Yuezhi , Mardirossian Narbe , Pokhilko Pavel , White Alec F. , Coons Marc P. , Dempwolff Adrian L. , Gan Zhengting , Hait Diptarka , Horn Paul R. , Jacobson Leif D. , Kaliman Ilya , Kussmann Jörg , Lange Adrian W. , Lao Ka Un , Levine Daniel S. , Liu Jie , McKenzie Simon C. , Morrison Adrian F. , Nanda Kaushik D. , Plasser Felix , Rehn Dirk R. , Vidal Marta L. , You Zhi-Qiang , Zhu Ying , Alam Bushra , Albrecht Benjamin J. , Aldossary Abdulrahman , Alguire Ethan , Andersen Josefine H. , Athavale Vishikh , Barton Dennis , Begam Khadiza , Behn Andrew , Bellonzi Nicole , Bernard Yves A. , Berquist Eric J. , Burton Hugh G. A. , Carreras Abel , Carter-Fenk Kevin , Chakraborty Romit , Chien Alan D. , Closser Kristina D. , Cofer-Shabica Vale , Dasgupta Saswata , de Wergifosse Marc , Deng Jia , Diedenhofen Michael , Do Hainam , Ehlert Sebastian , Fang Po-Tung , Fatehi Shervin , Feng Qingguo , Friedhoff Triet , Gayvert James , Ge Qinghui , Gidofalvi Gergely , Goldey Matthew , Gomes Joe , González-Espinoza Cristina E. , Gulania Sahil , Gunina Anastasia O. , Hanson-Heine Magnus W. D. , Harbach Phillip H. P. , Hauser Andreas , Herbst Michael F. , Hernández Vera Mario , Hodecker Manuel , Holden Zachary C. , Houck Shannon , Huang Xunkun , Hui Kerwin , Huynh Bang C. , Ivanov Maxim , Jász Ádám , Ji Hyunjun , Jiang Hanjie , Kaduk Benjamin , Kähler Sven , Khistyaev Kirill , Kim Jaehoon , Kis Gergely , Klunzinger Phil , Koczor-Benda Zsuzsanna , Koh Joong Hoon , Kosenkov Dimitri , Koulias Laura , Kowalczyk Tim , Krauter Caroline M. , Kue Karl , Kunitsa Alexander , Kus Thomas , Ladjánszki István , Landau Arie , Lawler Keith V. , Lefrancois Daniel , Lehtola Susi , Li Run R. , Li Yi-Pei , Liang Jiashu , Liebenthal Marcus , Lin Hung-Hsuan , Lin You-Sheng , Liu Fenglai , Liu Kuan-Yu , Loipersberger Matthias , Luenser Arne , Manjanath Aaditya , Manohar Prashant , Mansoor Erum , Manzer Sam F. , Mao Shan-Ping , Marenich Aleksandr V. , Markovich Thomas , Mason Stephen , Maurer Simon A. , McLaughlin Peter F. , Menger Maximilian F. S. J. , Mewes Jan-Michael , Mewes Stefanie A. , Morgante Pierpaolo , Mullinax J. Wayne , Oosterbaan Katherine J. , Paran Garrette , Paul Alexander C. , Paul Suranjan K. , Pavošević Fabijan , Pei Zheng , Prager Stefan , Proynov Emil I. , Rák Ádám , Ramos-Cordoba Eloy , Rana Bhaskar , Rask Alan E. , Rettig Adam , Richard Ryan M. , Rob Fazle , Rossomme Elliot , Scheele Tarek , Scheurer Maximilian , Schneider Matthias , Sergueev Nickolai , Sharada Shaama M. , Skomorowski Wojciech , Small David W. , Stein Christopher J. , Su Yu-Chuan , Sundstrom Eric J. , Tao Zhen , Thirman Jonathan , Tornai Gábor J. , Tsuchimochi Takashi , Tubman Norm M. , Veccham Srimukh Prasad , Vydrov Oleg , Wenzel Jan , Witte Jon , Yamada Atsushi , Yao Kun , Yeganeh Sina , Yost Shane R. , Zech Alexander , Zhang Igor Ying , Zhang Xing , Zhang Yu , Zuev Dmitry , Aspuru-Guzik Alán , Bell Alexis T. , Besley Nicholas A. , Bravaya Ksenia B. , Brooks Bernard R. , Casanova David , Chai Jeng-Da , Coriani Sonia , Cramer Christopher J. , Cserey György , DePrince A. Eugene , DiStasio Robert A. , Dreuw Andreas , Dunietz Barry D. , Furlani Thomas R. , Goddard William A. , Hammes-Schiffer Sharon , Head-Gordon Teresa , Hehre Warren J. , Hsu Chao-Ping , Jagau Thomas-C. , Jung Yousung , Klamt Andreas , Kong Jing , Lambrecht Daniel S. , Liang WanZhen , Mayhall Nicholas J. , McCurdy C. William , Neaton Jeffrey B. , Ochsenfeld Christian , Parkhill John A. , Peverati Roberto , Rassolov Vitaly A. , Shao Yihan , Slipchenko Lyudmila V. , Stauch Tim , Steele Ryan P. , Subotnik Joseph E. , Thom Alex J. W. , Tkatchenko Alexandre , Truhlar Donald G. , Van Voorhis Troy , Wesolowski Tomasz A. , Whaley K. Birgitta , Woodcock H. Lee , Zimmerman Paul M. , Faraji Shirin , Gill Peter M. W. , Head-Gordon Martin , Herbert John M. , Krylov Anna I. 
Published: August 2021

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.