License information

ViPErLEED

The ViPErLEED project aims to provide free and open software. However, because ViPErLEED is building on existing software, the ViPErLEED developers cannot grant permission to redistribute certain parts of the software. For inquiries or questions, please contact the ViPErLEED developers under info@viperleed.org.

All files in the main repository and all files authored by the ViPErLEED developers are licensed under the GPLv3. This explicitly includes the ViPErLEED Python package (viperleed.calc, gui, utils), ViPErLEED electronics (firmware, schematics, software) and the ViPErLEED ImageJ plugins.

The documentation for all parts of ViPErLEED is licensed under the CC BY 4.0 license.

TensErLEED

The v1.2 version of TensErLEED was published with the Computer Physics Communications User License , which requires users to reference the original article (Blum and Heinz [6]) in resulting publications.

The ViPErLEED developers have obtained explicit permission by the authors to use and distribute these codes as part of ViPErLEED. Others may not redistribute TensErLEED, without permission by the original authors.

Changes to the TensErLEED source code made by the ViPErLEED authors (i.e. the patches that constitute v1.6.1 onwards), are licensed under GPLv3 or later. The copyright to these changes remains with the ViPErLEED authors.

EEASISSS

Elastic Electron-Atom Scattering in Solids and Solid Surfaces (EEASISSS) is written and maintained by John O. Rundgren (jru@KTH.se) and used by ViPErLEED with permission by the author.

The author appreciates acknowledgement in publications by citation of the relevant works: Rundgren et al. [25], Rundgren [11], Rundgren [24].

Local-density-functional calculations of the energy of atoms

The program “Local-density-functional calculations of the energy of atoms” (viperleed-tensorleed/atomic_density_files/atomic.f) was written by Eric L. Shirley (NIST). The ViPErLEED authors have obtained permission from the author to include the program in the ViPErLEED package and release it under GPLv3 (or later). The copyright remains with Eric L. Shirley.

If you find this program useful in your research, the author appreciates acknowledgement by including the following attribution in resulting publications:

Eric L. Shirley, PhD Thesis, University of Illinois at Urbana-Champaign, 1991