Displaying core level spectra
The CASTEP Analysis dialog can be used to generate observable core level spectra based on electronic energies on the Monkhorst-Pack mesh of
k-points obtained during a calculation. Detailed analysis of the impact of calculation parameters (k-point set, number of empty bands, etc.)
on the accuracy of the spectra generated can be found in the core level spectroscopy theory topic.
Core level spectra can only be calculated for single atoms. One atom should be selected in the active 3D
Atomistic document before carrying out a core level spectroscopy analysis.
To create a core level spectrum
- Choose Modules | CASTEP | Analysis from the menu bar to open the CASTEP Analysis dialog.
- Select Core level spectroscopy from the list of properties.
- In the 3D Atomistic document containing the 3D periodic structure, select the atom for which you wish to simulate a core level spectrum. Click
the Atom Selection button on the CASTEP Analysis dialog to open the Atom
- Use the Results file selector to pick the results file or make the
seedname_EELS.castep file the
- Select the electron configuration of the Spectrum.
- Specify the Type of spectrum you want to calculate, options are Absorption
- Click the More... button to open the CASTEP EELS Analysis Options dialog.
- Set the Instrumental smearing value.
- Specify whether to take Lifetime effects into account by checking or unchecking the checkbox, if checked set the
Core level broadening value.
- Specify whether to take Include spin-orbit splitting by checking or unchecking the checkbox, if checked set the
Spin-orbit splitting value and close the CASTEP EELS Analysis Options dialog.
- Select the incident radiation polarization from the Calculation dropdown list. If you specify Polarized radiation
choose the direction of the Polarization of the incident radiation in fractional (lattice) coordinates.
- Make the 3D periodic structure the active document and click the View button.
- A new chart document,
seedname EELS.xcd, is created in the results folder and becomes the active document.
If you carry out several core level spectroscopy analyses, each new spectrum will be displayed in a new chart document.
Core level spectroscopy
Analyzing CASTEP results
Core level spectroscopy selection - CASTEP Analysis dialog
Accelrys Materials Studio 8.0 Help: Wednesday, December 17, 2014