Overview of Phonon Software 5.10

Open Project. Opens an existing Project, or starts a New Project. Project can be copied renamed, or deleted. There are ready examples under Import Model.

Symmetry and Unit Cell. In dialog Symmetry and Unit Cell one determines the crystal space group, lattice constants, and number of non-equivalent atoms in the primitive unit cell. As an example the crystal of Mg₂SiO₄ has been selected.

Particle Positions. In dialog Particles the fractional positions of non-equivalent atoms are inserted. This is sufficient information to build the crystal

View Crystallographic Unit Cell. Constructed crystal can be viewed.

Viewer. Mouse and keyboard are used to rotate, shift, magnify, and change the appearance of the unit cell.

Supercell Data. Defines the size and shape supercell.

Create. In menu Create the crystal structure is defined and the Hellmann-Feynman file converted into force constants.

Supercell and Hellmann-Feynman file. Defines supercell obtained as a result of optimization. Provides dialog for writing the HF file data.

Hellmann-Feynman file. Shows fragment of the Hellmann-Feynman file.

Analyze. Menu to compute and plot the lattice dynamics results.

Wave vectors. Wave vectors for Dispersion Relation plot. Calculated phonon dispersion curves are passing the points given in this table.

Phonon Dispersion Curves. Plot of phonon dispersion curves.

Intensity of Phonons. According to some combination of polarization vectors each phonon possesses some intensity. This intensity is defined in colour table from 0 till 100.

Intensity of Phonon Dispersion Curves as Colour. Plots phonon dispersion curves using colour as intensity. This intensity is defined in colour table.

Intensity of Phonon Dispersion Curves as Plot. Plots intensity of phonon dispersion curves at q=const. (red vertical line).

Animation of Phonon Mode. Selection of a phonon mode on the phonon dispersion relation plot opens the animator window which shows atomic motion of this mode.

Symmetries of phonon modes. Table of transverse phonon modes and their irreducible representations at k=0 wave vector calculated from polarization vectors.

Menu for Phonon Density of States. Options related with phonon density of states.

Phonon Density of States. Total and partial phonon density of states. Total (black), and partial for silicon (red), magnesium (green) and oxygen (blue)..

Menu for Thermodynamics. Options related with thermodynamical functions: internal energy, entropy, free energy, heat capacity, and thermal mean square displacements.

Menu for Neutron Scattering Spectra. Options related to intensity of coherent inelastic neutron scattering, inelastic incoherent scattering on single and polycrystal samples. Similar options exist for x-rays scattering.

Menu for Dielectric Properties. Options related to dielectric tensor, longitudinal optic / transverse optic (LO/TO) phonons and infrared absorption.

Many Windows. Phonon Software allows to display simultaneously many plots. Hence, the conclusions, hopefully, is easier to draw.