MOPAC

Last updated
MOPAC
Original author(s) James Stewart
Developer(s) Molecular Sciences Software Institute
Initial release1983;41 years ago (1983)
Stable release
22.1.1 / 29 January 2024;2 months ago (2024-01-29)
Repository github.com/openmopac/mopac
Written in Fortran
Operating system Linux, MacOS, Microsoft Windows
Available inEnglish
Type Computational chemistry
License LGPL 3.0
Website openmopac.net

MOPAC is a computer program used in computational chemistry. It is designed to implement semi-empirical quantum chemistry algorithms, and it runs on Windows, MacOS, and Linux. [1]

Contents

MOPAC2016 is the current version. MOPAC2016 is able to perform calculations on small molecules and enzymes using PM7, PM6, PM3, AM1, MNDO, and RM1. The Sparkle model (for lanthanide chemistry) [2] is also available. Academic users can use this program for free, whereas government and commercial users must purchase the software. [3]

MOPAC was largely written by Michael Dewar's research group at the University of Texas at Austin. [4] Its name is derived from Molecular Orbital PACkage, and it is also a pun on the Mopac Expressway that runs around Austin. [5]

MOPAC2007 included the new Sparkle/AM1, Sparkle/PM3, RM1 and PM6 models, with an increased emphasis on solid state capabilities. However, it does not have MINDO/3, PM5, analytical derivatives, the Tomasi solvation model or intersystem crossing. MOPAC2007 was followed by the release of MOPAC2009 in 2008, which presents many improved features. [6]

Later versions were no longer public-domain software, as were the earlier versions, such as MOPAC6 and MOPAC7. However, there were efforts to keep MOPAC7 working as open source software. An open source version of MOPAC7 for Linux is also available. [7] In 2006, the author of MOPAC, James Stewart, released a public-domain version of MOPAC7 entirely written in Fortran 90, called MOPAC7.1.

In 2022, MOPAC2016 was released as openMopac [8] and opened sourced under the LGPL license.

See also

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References

  1. "MOPAC". Stewart Computational Chemistry.
  2. "Lanthanide Complexes Computational Chemistry". Archived from the original on 2018-10-14. Retrieved 2006-12-08.
  3. "MOPAC2012 Brochure" (PDF). Stewart Computational Chemistry.
  4. Computational Chemistry, David Young, Wiley-Interscience, 2001. Appendix A. A.3.2 pg 342, MOPAC
  5. J. J. P. Stewart. "General Description of MOPAC". Stewart Computational Chemistry.
  6. "MOPAC2016 - Maintenance record".
  7. MOPAC7 Open Source Version
  8. "MOPAC released as open source".