Feature request: Support for CASTEP input and output files

[will9508]

Dear TDEP developers,

Thank you for developing and maintaining TDEP. It is a very useful framework for studying temperature-dependent lattice dynamics and anharmonic phonons.

I would like to suggest adding support for CASTEP. The current output formats include VASP, ABINIT, FHI-aims, SIESTA, Quantum ESPRESSO and PARSEC, but not CASTEP. Since CASTEP is widely used in the materials science community, especially in the UK, supporting it could broaden the potential user base.

In particular, it would be helpful if TDEP could read forces from CASTEP output files and also generate the corresponding displaced structures in CASTEP format.

Thank you for considering this suggestion.

Best regards

[mjv500]

Hi Will, good idea - we have no experience using CASTEP. Could you provide a pull request with an example input and at least the embryo of a hack to convert the E/F/stress data into the TDEP format? It's quite simple, as you have probably seen in the other parsers/converters. best Matthieu

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On Fri, Mar 6, 2026 at 8:39 PM will9508 ***@***.***> wrote: *will9508* created an issue (tdep-developers/tdep#171) <#171> Dear TDEP developers, Thank you for developing and maintaining TDEP. It is a very useful framework for studying temperature-dependent lattice dynamics and anharmonic phonons. I would like to suggest adding support for CASTEP. The current output formats include VASP, ABINIT, FHI-aims, SIESTA, Quantum ESPRESSO and PARSEC, but not CASTEP. Since CASTEP is widely used in the materials science community, especially in the UK, supporting it could broaden the potential user base. In particular, it would be helpful if TDEP could read forces from CASTEP output files and also generate the corresponding displaced structures in CASTEP format. Thank you for considering this suggestion. Best regards — Reply to this email directly, view it on GitHub <#171>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABWOT33BNJ37GQZEDPFMCK34PMSOFAVCNFSM6AAAAACWJ3UOSKVHI2DSMVQWIX3LMV43ASLTON2WKOZUGAZTKOBUGY2TSOI> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

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