dielectric_function¶
(
- data_context,
- **kwargs
)
The dielectric function describes the material response to an electric field.
The dielectric function is a fundamental concept that describes how a material responds to an external electric field. It is a frequency-dependent complex-valued 3x3 matrix that relates the polarization of a material to the applied electric field. The dielectric function is essential in understanding optical properties, such as refractive index and absorption.
There are many different ways to compute dielectric functions with VASP. This class provides a common interface to all of them. You can pass a selection argument to any of the methods of this class to select which dielectric function you are interested in. Please make sure the INCAR file you use is compatible with the setup.
The 3x3 matrix is symmetric so for the plotting routines, py4vasp uses only the six distinct components (xx, yy, zz, xy, xz, yz). The default is the isotropic dielectric function but you can also select specific components by providing one of the six components as selection.
path
plot
Almost same as the to_graph() function.
All arguments will be passed to to_graph. If the to_graph() would
produce multiple graphs this method will merge them into a single one.
read
selections
to_csv
(
- *args,
- filename:
str | Path= None, - **kwargs
)
Writes the data to a csv file.
Writes out a csv file for data stored in a dataframe generated with
the to_frame() method. Useful for creating external plots
for further analysis.
If no filename is provided a default filename is deduced from the name of the class.
Note that the filename must be a keyword argument, i.e., you explicitly
need to write filename=”name_of_file” because the arguments are passed
on to the to_graph() method. Please check the documentation of that
method to learn which arguments are allowed.
Parameters
- filename:
str | Path= None - Name of the csv file which the data is exported to.
to_dict
dict
Read the data into a dictionary.
Returns
dict- Contains the energies at which the dielectric function was evaluated and the dielectric tensor (3x3 matrix) at these energies.
to_frame
Dataframe
Convert data to pandas dataframe.
This will first convert use the to_graph() method to convert to a
Graph. All arguments are passed to that method. The resulting graph is then
converted to a dataframe.
Returns
Dataframe- Pandas dataframe corresponding to data in the graph
to_graph
str = None) → Graph
Read the data and generate a figure with the selected directions.
Parameters
- selection:
str= None - Specify along which directions and which components of the dielectric function you want to plot. Defaults to isotropic and both the real and the complex part. You can use the selections routine if you are not sure which options are available.
Returns
Graph- figure containing the dielectric function for the selected directions and components.
to_image
(
- *args,
- filename = None,
- **kwargs
)
Read the data and generate an image writing to the given filename.
The filetype is automatically deduced from the filename; possible are common raster (png, jpg) and vector (svg, pdf) formats. If no filename is provided a default filename is deduced from the name of the class and the picture has png format.
Note that the filename must be a keyword argument, i.e., you explicitly
need to write filename=”name_of_file” because the arguments are passed
on to the to_graph() method. Please check the documentation of that
method to learn which arguments are allowed.
to_plotly
Produces a graph and convertes it to a plotly figure.
The arguments to this function are passed on to the to_graph() method.
Takes the resulting graph and converts it to a plotly figure.