Population Analysis
By default castep will calculate the Mulliken Population analysis at the end of every calculation (the keyword popn_calculate is set to true by default).
Silicon
Here is a cell file. You can use the icon in the top right of the box to copy and paste the text. Save it in a file silicon.cell
%block lattice_abc
3.8 3.8 3.8
60 60 60
%endblock lattice_abc
!
! Atomic co-ordinates for each species.
! These are in fractional co-ordinates wrt to the cell.
!
%block positions_frac
Si 0.00 0.00 0.00
Si 0.25 0.25 0.25
%endblock positions_frac
!
! Analyse structure to determine symmetry
!
symmetry_generate
!
! Specify M-P grid dimensions for electron wavevectors (K-points)
!
kpoint_mp_grid 4 4 4
Here is a param file. You can use the icon in the top right of the box to copy and paste the text. Save it in a file silicon.param
xc_functional : LDA
cutoff_energy : 500 eV
spin_polarised : false
Run castep. Toward the end of the file silicon.castep you will find
Atomic Populations (Mulliken)
-----------------------------
Species Ion s p d f Total Charge (e)
==========================================================================
Si 1 1.356 2.644 0.000 0.000 4.000 0.000
Si 2 1.356 2.644 0.000 0.000 4.000 0.000
==========================================================================
Bond Population Length (A)
======================================================================
Si 1 -- Si 2 2.99 2.32702
======================================================================