# The Chronus Quantum software package

@article{WilliamsYoung2019TheCQ, title={The Chronus Quantum software package}, author={David B. Williams-Young and Alessio Petrone and Shichao Sun and Torin F. Stetina and Patrick J. Lestrange and Chad E. Hoyer and Daniel R. Nascimento and Lauren N. Koulias and Andrew Wildman and Joseph M. Kasper and Joshua J. Goings and Feizhi Ding and A. Eugene DePrince and Edward F. Valeev and Xiaosong Li}, journal={Wiley Interdisciplinary Reviews: Computational Molecular Science}, year={2019}, volume={10} }

The Chronus Quantum (ChronusQ) software package is an open source (under the GNU General Public License v2) software infrastructure which targets the solution of challenging problems that arise in ab initio electronic structure theory. Special emphasis is placed on the consistent treatment of time dependence and spin in the electronic wave function, as well as the inclusion of relativistic effects in said treatments. In addition, ChronusQ provides support for the inclusion of uniform finite…

## 37 Citations

### BDF: A relativistic electronic structure program package.

- Chemistry, PhysicsThe Journal of chemical physics
- 2020

Additional features of BDF include a maximum occupation method for finding excited states of Hartree-Fock/Kohn-Sham (HF/KS) equations, a very efficient localization of HF/KS and complete active space self-consistent field orbitals, and a unique solver for exterior and interior roots of large matrix eigenvalue problems.

### GQCP: The Ghent Quantum Chemistry Package.

- Computer Science, ChemistryThe Journal of chemical physics
- 2021

GQCP focuses on providing quantum chemical method developers with the computational "building blocks" that allow them to flexibly develop proof of principle implementations for new methods and applications up to the level of two-component spinor bases.

### Perspective:"Relativity + Correlation + QED = Experiment''

- Physics
- 2022

The ultimate goal of electronic structure calculations is to make the left and right hand sides of the titled “equation” as close as possible. This requires high-precision treatment of relativistic,…

### Essentials of relativistic quantum chemistry.

- Physics, EducationThe Journal of chemical physics
- 2020

The three aspects of electronic structure calculations, i.e., relativity, correlation, and QED, will be highlighted.

### Modeling Ultrafast Electron Dynamics in Strong Magnetic Fields Using Real-Time Time-Dependent Electronic Structure Methods

- Chemistry, PhysicsJournal of chemical theory and computation
- 2021

The complex evolution of the absorption spectra with magnetic field is rationalized using the molecular orbital pair decomposition analysis, which provides crucial insight in strong fields where the spectra are radically different from their zero-field counterparts.

### Free and open source software for computational chemistry education

- Computer ScienceWIREs Computational Molecular Science
- 2021

It is demonstrated that a decentralized model for teaching computational chemistry is now possible thanks to FOSS packages, enabling students to perform reasonable modeling on their own computing devices in the bring your own device (BYOD) scheme.

### Relativistic two-component projection-based quantum embedding for open-shell systems.

- PhysicsThe Journal of chemical physics
- 2020

The relativistic embedding formalism introduced in this work is well suited for efficient modeling of open-shell systems containing late transition metal, lanthanide, and actinide molecular complexes.

### Real-Time Time-Dependent Nuclear-Electronic Orbital Approach: Dynamics Beyond the Born-Oppenheimer Approximation.

- PhysicsThe journal of physical chemistry letters
- 2020

This work derives and implements a real-time NEO (RT-NEO) approach based on time-dependent Hatree-Fock or density functional theory, in which both the electronic and nuclear degrees of freedom are propagated in a time- dependent variational framework.

### Nuclear-electronic orbital methods: Foundations and prospects.

- Physics, ChemistryThe Journal of chemical physics
- 2021

The conceptual simplicity and computational efficiency of the NEO approach will enhance its accessibility and applicability to diverse chemical and biological systems.

### Solvated Nuclear-Electronic Orbital Structure and Dynamics.

- Chemistry, PhysicsJournal of chemical theory and computation
- 2022

Nonadiabatic dynamical processes such as proton-coupled electron transfer and excited state intramolecular proton transfer have been the subject of much research. One of the promising theoretical…

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