Q-chem 2.0: A high-performance ab initio electronic structure program package

Q-Chem 2.0 is a new release of an electronic structure program package, cap able of performing first principles calculations on the ground and excited states of molecules using both density functional theory and wave function- based methods. A review of the technical features contained within Q-Chem 2 .0 is presented. This article contains brief descriptive discussions of the key physical features of all new algorithms and theoretical models, togeth er with sample calculations that illustrate their performance. (C) 2000 Joh n Wiley & Sons, Inc.