QCMaquis 4.0: Multi-Purpose Electronic, Vibrational, and Vibronic Structure and Dynamics Calculations with the Density Matrix Renormalization Group

TL;DR

QCMaquis 4.0 is an advanced quantum chemistry software enabling comprehensive electronic, vibrational, and vibronic calculations using DMRG, with new features like time propagation, transcorrelation, and Python integration.

Contribution

The paper introduces new capabilities in QCMaquis 4.0, including time-dependent DMRG, transcorrelated methods, and a Python interface, expanding its application scope.

Findings

Demonstration of time propagation of matrix product states.

Implementation of transcorrelated electronic structure calculations.

Integration of a Python wrapper for easier interfacing.

Abstract

QCMaquis is a quantum chemistry software package for general molecular structure calculations in a matrix product state/matrix product operator formalism of the density matrix renormalization group (DMRG). It supports a wide range of features for electronic structure, multi-component (pre-Born-Oppenheimer), anharmonic vibrational structure, and vibronic calculations. In addition to the ground and excited state solvers, QCMaquis allows for time propagation of matrix product states based on the tangent-space formulation of time-dependent DMRG. The latest developments include transcorrelated electronic structure calculations, very recent vibrational and vibronic models, and a convenient Python wrapper, facilitating the interface with external libraries. This paper reviews all the new features of QCMaquis and demonstrates them with new results.