The General Atomic and Molecular Electronic Structure System (GAMESS): Novel Methods on Novel Architectures.

Area of Science:

• Computational chemistry
• High-performance computing
• Quantum chemistry

Background:

• GAMESS (General Atomic and Molecular Electronic Structure System) has focused on enhancing computational efficiency.
• Advanced computer architectures, including CPUs and accelerators, present opportunities for computational chemistry.
• Accurate quantum chemical calculations, particularly for correlated methods, are computationally demanding.

Purpose of the Study:

• To detail recent advancements in GAMESS software over the past five years.
• To highlight the development of high-performance codes for modern computing architectures.
• To introduce new functionalities for analyzing complex wave functions and discuss software maintenance.

Main Methods:

• Development of high-performance codes leveraging advanced CPU and accelerator architectures.
• Implementation of density fitting and fragmentation methods to reduce computational scaling for correlated methods.
• Creation of novel codes optimized for graphical processing units (GPUs) and other accelerators.
• Introduction of quasi-atomic orbital (QTAO) analysis for wave function interpretation.

Main Results:

• Effective utilization of advanced computer architectures for quantum chemistry calculations.
• Significant reduction in the computational cost of well-correlated methods through density fitting and fragmentation.
• Optimized performance on GPUs and other accelerators for complex electronic structure calculations.
• Development of QTAO analysis as a tool for understanding covalent bonding within wave functions.

Conclusions:

• GAMESS has successfully adapted to and exploited modern high-performance computing architectures.
• New computational strategies enhance the efficiency and applicability of advanced quantum chemical methods.
• Quasi-atomic orbital analysis provides a valuable, unbiased method for interpreting chemical bonds.
• Best practices for GAMESS maintenance and distribution ensure continued usability and development.