# What is GAMESS? **URL:** \ **Category:** Q&A\ **Tags:** computational-chemistry, gamess, researcher\ **Created:** [November 28, 2018, 1:22am UTC](https://ask.cyberinfrastructure.org/t/what-is-gamess/662 "2018-11-28T01:22:25Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![vsoch](https://ask.cyberinfrastructure.org/user_avatar/ask.cyberinfrastructure.org/vsoch/32/112_2.png) [@vsoch](https://ask.cyberinfrastructure.org/u/vsoch)\ **Post date:** [November 28, 2018, 1:22am UTC](https://ask.cyberinfrastructure.org/t/what-is-gamess/662/1 "2018-11-28T01:22:25Z")
There is a long list of questions that are asking about something called GAMESS, for example: - [Is there a way to reduce the amount of disk files GAMESS uses, or even run the calculations entirely in RAM?](https://ask.cyberinfrastructure.org/t/is-there-a-way-to-reduce-the-amount-of-disk-files-gamess-uses-or-even-run-the-calculations-entirely-in-ram/261) - [Does GAMESS benefit from running calculations on multiple compute nodes? If so, what methods scale the best across many compute nodes on a cluster?](https://ask.cyberinfrastructure.org/t/does-gamess-benefit-from-running-calculations-on-multiple-compute-nodes-if-so-what-methods-scale-the-best-across-many-compute-nodes-on-a-cluster/262) - [How many MPI ranks should I request for a GAMESS calculation?](https://ask.cyberinfrastructure.org/t/how-many-mpi-ranks-should-i-request-for-a-gamess-calculation/260) - [How can I restart my GAMESS calculation and resubmit?](https://ask.cyberinfrastructure.org/t/how-can-i-restart-my-gamess-calculation-and-resubmit/259) - [How can I determine how much memory I need before submitting my GAMESS calculation?](https://ask.cyberinfrastructure.org/t/how-can-i-determine-how-much-memory-i-need-before-submitting-my-gamess-calculation/258) Can anyone tell me what exactly GAMESS is? I’d like to know a good definition, use cases in HPC, and alternatives to it. Thank you! ---
**Author:** ![jma](https://ask.cyberinfrastructure.org/user_avatar/ask.cyberinfrastructure.org/jma/32/303_2.png) [@jma](https://ask.cyberinfrastructure.org/u/jma)\ **Post date:** [November 28, 2018, 4:11am UTC](https://ask.cyberinfrastructure.org/t/what-is-gamess/662/2 "2018-11-28T04:11:51Z")
@srpruitt Can you please help us out with this one? Thank you! ---
**Author:** ![wirawan0](https://ask.cyberinfrastructure.org/user_avatar/ask.cyberinfrastructure.org/wirawan0/32/362_2.png) [@wirawan0](https://ask.cyberinfrastructure.org/u/wirawan0)\ **Post date:** [March 8, 2019, 4:37pm UTC](https://ask.cyberinfrastructure.org/t/what-is-gamess/662/3 "2019-03-08T16:37:57Z")
GAMESS is a computational chemistry software package developed by Gordon research group at Iowa State University. This is the website of the project: [https://www.msg.chem.iastate.edu/gamess/](https://www.msg.chem.iastate.edu/gamess/) It is written in Fortran, and it is capable of running massively parallel. This is the summary of the capabilities of the software, from the authors’ website: > GAMESS is a program for _ab initio_ molecular quantum chemistry. Briefly, GAMESS can compute SCF wavefunctions ranging from RHF, ROHF, UHF, GVB, and MCSCF. Correlation corrections to these SCF wavefunctions include Configuration Interaction, second order perturbation Theory, and Coupled-Cluster approaches, as well as the Density Functional Theory approximation. Excited states can be computed by CI, EOM, or TD-DFT procedures. Nuclear gradients are available, for automatic geometry optimization, transition state searches, or reaction path following. Computation of the energy hessian permits prediction of vibrational frequencies, with IR or Raman intensities. Solvent effects may be modeled by the discrete Effective Fragment potentials, or continuum models such as the Polarizable Continuum Model. Numerous relativistic computations are available, including infinite order two component scalar relativity corrections, with various spin-orbit coupling options. The Fragment Molecular Orbital method permits use of many of these sophisticated treatments to be used on very large systems, by dividing the computation into small fragments. Nuclear wavefunctions can also be computed, in VSCF, or with explicit treatment of nuclear orbitals by the NEO code. It is distributed as source code, but not an open source project (i.e. no source code distribution to outside parties). You need to request access to the source code from the authors and get your request approved. Please see here for the full license terms: [https://www.msg.chem.iastate.edu/gamess/License\_Agreement.html](https://www.msg.chem.iastate.edu/gamess/License_Agreement.html) ---
**Author:** ![vsoch](https://ask.cyberinfrastructure.org/user_avatar/ask.cyberinfrastructure.org/vsoch/32/112_2.png) [@vsoch](https://ask.cyberinfrastructure.org/u/vsoch)\ **Post date:** [May 11, 2019, 1:26am UTC](https://ask.cyberinfrastructure.org/t/what-is-gamess/662/4 "2019-05-11T01:26:27Z")
I haven’t heard about this model (closed source with contact + permission) - what kind of LICENSE does it have?