Molcas 8

Molcas is an ab initio quantum chemistry software package developed by scientists to be used by scientists. The basic philosophy is is to be able to treat general electronic structures for molecules consisting of atoms from most of the periodic table. As such, the primary focus of the package is on multiconfigurational methods with applications typically connected to the treatment of highly degenerate states.

Key aspects of Molcas:

  • Fast, accurate, and robust code
  • Free support and updates
Molcas is not a black box tool. The user should be an educated quantum chemist, with some knowledge about the different quantum chemical models in use today, their application areas and their inherent accuracy. The MOLCAS group arranges regular MOLCAS workshops, which teaches how to use the software.

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  • 170317 Molcas 8.2 is ready for release!
    Molcas 8 users (with a valid licence) can download binaries for Molcas 8.2 using the access to User area. To obtain the source code, send e-mail to
  • 160919 New book Multiconfigurational Quantum Chemistry
  • 141230 An update for ANO-RCC basis set for Eu and Th
  • 151112 Molcas Forum is launched
  • If you would like to join Molcas developer's team, submit your project here.