dfttk.quasi_harmonic

QuasiHarmonic class for storing, processing, and plotting quasi-harmonic data.

class dfttk.quasi_harmonic.QuasiHarmonic(number_of_atoms, volumes, temperatures)[source]

Bases: object

Stores, processes, and plots quasi-harmonic data for a given system.

process(method, energies, vibrational_helmholtz_energies, vibrational_entropies, vibrational_heat_capacities, electronic_helmholtz_energies=None, electronic_entropies=None, electronic_heat_capacities=None, P=0.0, eos_name='BM4')[source]

Calculates and stores the quasiharmonic properties for a given method.

Parameters:

  • method (str) – Calculation method.

  • energies (ndarray) – Static energies (shape: [n_volumes]).

  • vibrational_helmholtz_energies (ndarray) – Vibrational helmholtz energies (shape: [n_temps, n_volumes]).

  • vibrational_entropies (ndarray) – Vibrational entropies (shape: [n_temps, n_volumes]).

  • vibrational_heat_capacities (ndarray) – Vibrational heat capacities (shape: [n_temps, n_volumes]).

  • electronic_helmholtz_energies (ndarray) – Electronic helmholtz energies (shape: [n_temps, n_volumes]). Defaults to None.

  • electronic_entropies (ndarray) – Electronic entropies (shape: [n_temps, n_volumes]). Defaults to None.

  • electronic_heat_capacities (ndarray) – Electronic heat capacities (shape: [n_temps, n_volumes]). Defaults to None.

  • P (float) – Pressure in GPa. Defaults to 0.00.

  • eos_name (str) – Equation of state to use. Defaults to “BM4”.

Raises:

  • ValueError – If the array does not have the expected shape.

  • ValueError – If P is negative.

  • ValueError – If eos_name is not a supported EOS function.

Return type:

None

plot(method, P, plot_type, selected_temperatures=None)[source]

Generate plots for the quasiharmonic data.

Parameters:

  • method (str) – Calculation method.

  • P (float) – Pressure in GPa.

  • plot_type (str) – Type of plot to generate.

  • selected_temperatures (ndarray) – Specific temperatures to plot for helmholtz_energy_pv.

Returns:

Plotly figure object for the selected data.

Return type:

Figure

Raises:

  • ValueError – If the requested method or pressure data is not available.

  • ValueError – If plot_type is not recognized.