Qbox home page

Welcome to qboxcode.org, home of the Qbox first-principles molecular dynamics code.

Qbox is a C++/MPI scalable parallel implementation of first-principles molecular dynamics (FPMD) based on the plane-wave, pseudopotential formalism. Qbox is designed for operation on large parallel computers.

Qbox is now available on the ESLAB GitLab server
http://scherzo.ucdavis.edu/qbox/qbox-public

It is also available on github at https://github.com/qboxcode

[2024-08-20] Version 1.78.2 is available.
Includes calculations of dipoles in arbitrary unit cells and improved accuracy of MLWF center positions in non-cubic cells.

[2023-10-03] Version 1.76.1 is available.

[2023-02-26] Version 1.75.1 is available.
Enable large samples

[2022-09-25] Version 1.75.0 is available.
Update of band alignment functionality

[2022-07-18] Version 1.74.4 is available.
Python compatibility release.

Qbox features include First-Principles Molecular Dynamics in the presence of arbitrary external electric fields, range-separated and HSE hybrid density functionals and the BHandHLYP functional, the implementation of the B3LYP functional for spin-polarized systems, calculations of the partial charge/spin in atom-centered spheres, and the option to execute arbitrary commands at regular intervals during MD simulations.

Qbox uses various types of pseudopotentials to represent electron-ion interactions. The SG15 collection of Optimized Norm Conserving Vanderbilt (ONCV) pseudopotentials is available at http://www.quantum-simulation.org/potentials. The SG15 potentials were optimized to reproduce all-electron calculations with high accuracy. The potentials are described in M. Schlipf and F. Gygi, Comput. Phys. Comm. 196, 36-44 (2015) http://dx.doi.org/10.1016/j.cpc.2015.05.011. Other pseudopotentials (HSCV, BHS) are available at http://quantum-simulation.org/potentials Pseudootentials from the pseudo-dojo collection http://pseudo-dojo.org can be used by translating them from UPF format to QSO format using the upf2qso program provided in the Qbox distribution in the util directory.

Documentation

See online documentation.
The design of Qbox is discussed in the following architecture paper (IBM J. Res. Dev. 52 p.137 (2008)).

Building Qbox

build instructions.

Qbox tools

A set of tools is available for post-processing and visualization of Qbox output.

Qbox output format

Qbox output conforms to the XML Schema described at http://www.quantum-simulation.org. This format is supported by the NOMAD repository https://repository.nomad-coe.eu

Qbox forum

A forum dedicated to questions regarding Qbox installation and use is available at http://qboxcode.org/qbox-list

Acknowledgement

Qbox is developed and maintained at the University of California Davis. Development is currently supported by a collaboration with the DOE Midwest Integrated Center for Computational Materials. Previous support was provided by the U.S. Department of Energy, Office of Basic Energy Sciences under grant DE-SC0008938.