MLRCIssc

MLRCIssc is a software tool developed by the University of California, Irvine, designed for the analysis of molecular quantum chemistry. It is an implementation of the Multi-Reference Configuration Interaction (MRCI) method, which is a post-Hartree-Fock method used to calculate the electronic structure of molecules. The MRCI method is particularly useful for systems where static correlation is significant, such as in transition metal complexes and molecules with multiple unpaired electrons.

The software is written in Fortran and is designed to be efficient and scalable, making it suitable for large-scale calculations. It supports a variety of basis sets and can be used to calculate a wide range of molecular properties, including energies, gradients, and Hessians. MLRCIssc is also capable of performing geometry optimizations and frequency calculations, making it a versatile tool for computational chemists.

The software is freely available for academic use and can be downloaded from the University of California, Irvine's website. It is distributed under the GNU General Public License, which allows for free use, modification, and distribution. The software is maintained and updated by a team of researchers at the University of California, Irvine, who are dedicated to improving its performance and functionality.