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Modern quantum chemistry with [Open]Molcas Cite as: J. Chem. Phys. 152, 214117 (2020); https://doi.org/10.1063/5.0004835 Submitted: 17 February 2020 . Accepted: 11 May 2020 . Published Online: 05 June 2020 Francesco Aquilante , Jochen Autschbach , Alberto Baiardi , Stefano Battaglia , Veniamin A. Borin , Liviu F. Chibotaru , Irene Conti , Luca De Vico , Mickaël Delcey , Ignacio Fdez. Galván , Nicolas Ferré , Leon Freitag , Marco Garavelli , Xuejun Gong , Stefan Knecht , Ernst D. Larsson , Roland Lindh , Marcus Lundberg , Per Åke Malmqvist , Artur Nenov , Jesper Norell , Michael Odelius , Massimo Olivucci , Thomas B. Pedersen , Laura Pedraza-González , Quan M. Phung , Kristine Pierloot , Markus Reiher , Igor Schapiro , Javier Segarra-Martí , Francesco Segatta , Luis Seijo , Saumik Sen , Dumitru-Claudiu Sergentu , Christopher J. Stein , Liviu Ungur , Morgane Vacher , Alessio Valentini , and Valera Veryazov COLLECTIONS Paper published as part of the special topic on Electronic Structure Software Note: This article is part of the JCP Special Topic on Electronic Structure Software. ARTICLES YOU MAY BE INTERESTED IN Dalton Project: A Python platform for molecular- and electronic-structure simulations of complex systems The Journal of Chemical Physics 152, 214115 (2020); https://doi.org/10.1063/1.5144298 The ORCA quantum chemistry program package The Journal of Chemical Physics 152, 224108 (2020); https://doi.org/10.1063/5.0004608 Coupled-cluster techniques for computational chemistry: The CFOUR program package The Journal of Chemical Physics 152, 214108 (2020); https://doi.org/10.1063/5.0004837 J. Chem. Phys. 152, 214117 (2020); https://doi.org/10.1063/5.0004835 152, 214117 © 2020 Author(s). The Journal ARTICLE of Chemical Physics scitation.org/journal/jcp Modern quantum chemistry with [Open]Molcas Cite as: J. Chem. Phys. 152, 214117 (2020); doi: 10.1063/5.0004835 Submitted: 17 February 2020 • Accepted: 11 May 2020 • Published Online: 5 June 2020 Francesco Aquilante,1,a) Jochen Autschbach,2,b) Alberto Baiardi,3,c) Stefano Battaglia,4,d) Veniamin A. Borin,5,e) Liviu F. Chibotaru,6,f) Irene Conti,7,g) Luca De Vico,8,h) Mickaël Delcey,9,i) Ignacio Fdez. Galván,4,j) Nicolas Ferré,10,k) Leon Freitag,3,l) Marco Garavelli,7,m) Xuejun Gong,11,n) Stefan Knecht,3,o) Ernst D. Larsson,12,p) Roland Lindh,4,q) Marcus Lundberg,9,r) Per Åke Malmqvist,12,s) Artur Nenov,7,t) Jesper Norell,13,u) Michael Odelius,13,v) Massimo Olivucci,8,14,w) Thomas B. Pedersen,15,x) Laura Pedraza-González,8,y) Quan M. Phung,16,z) Kristine Pierloot,6,aa) Markus Reiher,3,ab) Igor Schapiro,5,ac) Javier Segarra-Martí,17,ad) Francesco Segatta,7,ae) Luis Seijo,18,af) Saumik Sen,5,ag) Dumitru-Claudiu Sergentu,2,ah) Christopher J. Stein,3,ai) Liviu Ungur,11,aj) Morgane Vacher,19,ak) Alessio Valentini,20,al) and Valera Veryazov12,am) AFFILIATIONS 1 Theory and Simulation of Materials (THEOS) and National Centre for Computational Design and Discovery of Novel Materials (MARVEL), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland 2 Department of Chemistry, University at Buffalo, Buffalo, New York 14260-3000, USA 3 Laboratory of Physical Chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, Switzerland 4 Department of Chemistry – BMC, Uppsala University, P.O. Box 576, SE-751 23 Uppsala, Sweden 5 Fritz Haber Center for Molecular Dynamics Research, Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel 6 Department of Chemistry, KU Leuven, Celestijnenlaan 200F, 3001 Leuven, Belgium 7 Dipartimento di Chimica Industriale “Toso Montanari”, Università di Bologna, Viale del Risorgimento 4, Bologna I-40136, Italy 8 Dipartimento di Biotecnologie, Chimica e Farmacia, Università degli Studi di Siena, via Aldo Moro 2, 53100 Siena, Italy 9 Department of Chemistry – Ångström Laboratory, Uppsala University, SE-751 21 Uppsala, Sweden 10Aix-Marseille University, CNRS, Institut Chimie Radicalaire, Marseille, France 11 Department of Chemistry, University of Singapore, 3 Science Drive 3, 117543 Singapore 12Division of Theoretical Chemistry, Lund University, P.O. Box 124, Lund 22100, Sweden 13Department of Physics, AlbaNova University Center, Stockholm University, SE-106 91 Stockholm, Sweden 14Department of Chemistry, Bowling Green State University, Bowling Green, Ohio 43403, USA 15Hylleraas Centre for Quantum Molecular Sciences, Department of Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway 16Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8602, Japan 17Department of Chemistry, Molecular Sciences Research Hub, Imperial College London, White City Campus, 80 Wood Lane, London W12 0BZ, United Kingdom 18Departamento de Química, Instituto Universitario de Ciencia de Materiales Nicolás Cabrera, and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain 19Laboratoire CEISAM - UMR CNRS 6230, Université de Nantes, 44300 Nantes, France 20Theoretical Physical Chemistry, Research Unit MolSys, Université de Liège, Allée du 6 Août, 11, 4000 Liège, Belgium Note: This article is part of the JCP Special Topic on Electronic Structure Software. a)Electronic mail: [email protected] b)Electronic mail: [email protected] c)Electronic mail: [email protected] d)Electronic mail: [email protected] e)Electronic mail: [email protected] f)Electronic mail: [email protected] J. Chem. Phys. 152, 214117 (2020); doi: 10.1063/5.0004835 152, 214117-1 © Author(s) 2020 The Journal ARTICLE of Chemical Physics scitation.org/journal/jcp g)Electronic mail: [email protected] h)Electronic mail: [email protected] i)Electronic mail: [email protected] j)Electronic mail: [email protected] k)Electronic mail: [email protected] l)Electronic mail: [email protected] m)Electronic mail: [email protected] n)Electronic mail: [email protected] o)Electronic mail: [email protected] p)Electronic mail: [email protected] q)Electronic mail: [email protected] r)Electronic mail: [email protected] s)Electronic mail: [email protected] t)Electronic mail: [email protected] u)Electronic mail: [email protected] v)Electronic mail: [email protected] w)Electronic mail: [email protected] x)Electronic mail: [email protected] y)Electronic mail: [email protected] z)Electronic mail: [email protected] aa)Electronic mail: [email protected] ab)Electronic mail: [email protected] ac)Electronic mail: [email protected] ad)Electronic mail: [email protected] ae)Electronic mail: [email protected] af)Electronic mail: [email protected] ag)Electronic mail: [email protected] ah)Electronic mail: [email protected] ai)Electronic mail: [email protected] aj)Electronic mail: [email protected] ak)Electronic mail: [email protected] al)Electronic mail: [email protected] am)Author to whom correspondence should be addressed: [email protected] ABSTRACT MOLCAS/OpenMolcas is an ab initio electronic structure program providing a large set of computational methods from Hartree–Fock and density functional theory to various implementations of multiconfigurational theory. This article provides a comprehensive overview ofthe main features of the code, specifically reviewing the use of the code in previously reported chemical applications as well as morerecent applications including the calculation of magnetic properties from optimized density matrix renormalization group wave functions. © 2020 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/5.0004835., s I. INTRODUCTION a large set of either well-established or newly developed codes. In addition to functionality from the scientific point of view, the codes Modern quantum chemistry is impossible without a versa- are very different with respect to performance, the need of hardware tile computational software, which includes calculation of integrals, resources, documentation, and user friendliness. optimization of wave functions, and computation of properties. Not As a general purpose package for quantum chemical calcula- surprisingly, computational codes in the field are grouping into large tions, MOLCAS has made a long journey from a collection of home- packages, which simplifies the development process and their usage. made codes to professional software with distributed development, The list of quantum chemistry computer programs, maintained automatic verification, user support, etc. Recently, the vast majority at Wikipedia,1 contains almost one hundred different computational of codes in MOLCAS have been released as open source—the Open- codes with a large overlap in the functionality. Even in a narrow Molcas project. This package is user-friendly and ready-to-use, and field of codes, computing the electronic structure of the ground is also a developers’ platform. While OpenMolcas is a free-of-charge and excited states of molecules, a researcher can choose between package, with web based community support, the MOLCAS package J. Chem. Phys. 152, 214117 (2020); doi: 10.1063/5.0004835 152, 214117-2 © Author(s) 2020 The Journal ARTICLE of Chemical Physics scitation.org/journal/jcp is a licensed
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