MOLCAS—a software for multiconfigurational quantum chemistry calculations

Abstract

AbstractAt variance, with most of the quantum chemistry software presently available, MOLCAS is a package that is specialized in multiconfigurational wave function theory (MC‐WFT) rather than density functional theory (DFT). Given the much higher algorithmic complexity of MC‐WFT versus DFT, an extraordinary effort needs to be made from the programming point of view to achieve state‐of‐the‐art performance for large‐scale calculations. In particular, a robust and efficient implementation of the Cholesky decomposition techniques for handling two‐electron integrals has been developed which is unique to MOLCAS. Together with this ‘Cholesky infrastructure’, a powerful and multilayer graphical and scripting user interface is available, which is an essential ingredient for the setup of MC‐WFT calculations. These two aspects of the MOLCAS software constitute the focus of the present report. © 2012 John Wiley & Sons, Ltd.This article is categorized under: Software > Quantum Chemistry