Phonopy is an open source package of phonon calculations based on the supercell approach.

  • Phonon dispersion relation (band structure)
  • Phonon DOS and partial-DOS
  • Phonon thermal properties, free energy, heat capacity, and entropy
  • Phonon group velocity
  • Thermal expansion and heat capacity at constant pressure within quasi-harmonic approximation (phonopy-qha)
  • Mode Grüneisen parameters (gruneisen)
  • Non-analytical-term correction, LO-TO splitting (Born effective charges and dielectric constant are required.)
  • Animation of normal modes for crystal viewers
  • Characters of irreducible representations of normal modes
  • Crystal symmetry tools
  • Python module (Phonopy can be used in python script.)
  • Graphical plots

i0 i1

i2 i3

Interfaces for calculators

For the other calculators, input files under certain formats (force sets or force constants) are required. But the interfaces for popular calculators may be implemented if requested.

Mailing list

For questions, bug reports, and comments, please visit following mailing list:


Message body including attached files has to be smaller than 300 KB.


New BSD from version 1.3.

(LGPL from ver. 0.9.3 to version 1.2.1., GPL to version 0.9.2.)