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Updated: Dec 23, 2025

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry

Published on: April 8, 2020

Recent developments in the general atomic and molecular electronic structure system.

Giuseppe M J Barca¹, Colleen Bertoni², Laura Carrington³

¹Research School of Computer Science, Australian National University, Canberra, ACT 2601, Australia.

The Journal of Chemical Physics

|April 24, 2020

Summary

This summary is machine-generated.

This study details new features in GAMESS (General Atomic and Molecular Electronic Structure System) and its C++ library, LibCChem, including advanced computational chemistry methods and GPU acceleration. It also covers software development and future directions.

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Area of Science:

Computational Chemistry
Quantum Chemistry
Materials Science

Background:

GAMESS (General Atomic and Molecular Electronic Structure System) is a widely used computational chemistry software.
LibCChem is the associated C++ library enabling parallel and GPU computations.
Advancements in computational power necessitate efficient algorithms and hardware utilization.

Purpose of the Study:

To present recently implemented features in GAMESS and LibCChem.
To discuss the integration of advanced computational methods and hardware accelerators.
To provide insights into the maintenance and future development of the software suite.

Main Methods:

Implementation of fragmentation methods (FMO, EFP, EFMO).
Development of hybrid MPI/OpenMP approaches for Hartree-Fock calculations.
Inclusion of resolution of the identity (RI) second-order perturbation theory (MP2).
Addition of new coupled cluster theory methods.
Integration of multiple levels of density functional theory (DFT) and tight-binding (TB) theory.
Exploration of graphical processing unit (GPU) acceleration via LibCChem.

Main Results:

Successful implementation of diverse fragmentation techniques for large molecular systems.
Enhanced performance for Hartree-Fock calculations using hybrid parallelization.
Accurate and efficient electronic structure calculations through RI-MP2 and advanced coupled cluster methods.
Expanded capabilities with DFT and TB methods for various chemical problems.
Demonstrated utility of GPUs for accelerating complex quantum chemistry computations.

Conclusions:

The latest GAMESS and LibCChem versions offer significant improvements in computational efficiency and methodology.
The strategic use of accelerators like GPUs is crucial for tackling increasingly complex chemical problems.
Ongoing development and maintenance ensure the continued relevance and power of the GAMESS software suite.