ORBKIT: A modular python toolbox for cross-platform postprocessing of quantum chemical wavefunction data

• Published in: Journal of computational chemistry Vol. 37; no. 16; pp. 1511 - 1520
• Main Authors: Hermann, Gunter, Pohl, Vincent, Tremblay, Jean Christophe, Paulus, Beate, Hege, Hans-Christian, Schild, Axel
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 15.06.2016; Wiley Subscription Services, Inc
• Subjects: Computer programming; Data processing; electron density; electronic structure; Electronics; grid representation of one-electron quantities; molecular orbital ordering; molecular visualization; quantum chemical calculation; Quantum physics; molecular orbital ordering; electron density; molecular visualization; quantum chemical calculation; electronic structure; grid representation of one-electron quantities
• ISSN: 0192-8651; 1096-987X
• DOI: 10.1002/jcc.24358

ORBKIT is a toolbox for postprocessing electronic structure calculations based on a highly modular and portable Python architecture. The program allows computing a multitude of electronic properties of molecular systems on arbitrary spatial grids from the basis set representation of its electronic wavefunction, as well as several grid‐independent properties. The required data can be extracted directly from the standard output of a large number of quantum chemistry programs. ORBKIT can be used as a standalone program to determine standard quantities, for example, the electron density, molecular orbitals, and derivatives thereof. The cornerstone of ORBKIT is its modular structure. The existing basic functions can be arranged in an individual way and can be easily extended by user‐written modules to determine any other derived quantity. ORBKIT offers multiple output formats that can be processed by common visualization tools (VMD, Molden, etc.). Additionally, ORBKIT possesses routines to order molecular orbitals computed at different nuclear configurations according to their electronic character and to interpolate the wavefunction between these configurations. The program is open‐source under GNU‐LGPLv3 license and freely available at https://github.com/orbkit/orbkit/. This article provides an overview of ORBKIT with particular focus on its capabilities and applicability, and includes several example calculations. © 2016 Wiley Periodicals, Inc. ORBKIT is an open‐source toolbox for postprocessing electronic structure calculations. Based on a highly modular and portable Python architecture, it comes both as a standalone program and a function library. The program allows computing electronic properties of molecular systems on arbitrary spatial grids from the output of standard quantum chemistry programs.