Molecular Orbital (MO) projected Density-of-States - MolPDOS

Basics

This mode allows to generate projections and pDOS plots with respect to any molecular orbital (MO). To run it one just has to add calculate_modos=true keyword to <seed>.param file.

The projection data is produced by CASTEP after the SCF task and is written to files called <seed>.modos_state_<#>_<#>, where the two numbers correspond to the number and the spin of the specified reference orbital from the reference checkfile.

At the end of the <seed>.castep file the projection is commented in the following way:

             Calculating MODOS weights               
 +-------------------INPUT PARAMETERS-------------------+
Taking band from model   N2-base.check                                                                                                                                                                                                                                                   
  MODOS state               1
  MODOS band  nr.           5
  MODOS band has spin       1
  MODOS state               2
  MODOS band  nr.           6
  MODOS band has spin       1
|DeltaSCF| Population of state:     5     1   1.000000
|DeltaSCF| Population of state:     6     1   0.000000
 Writing file   N2-modos.modos_state_5_1
 Writing file   N2-modos.modos_state_6_1

These files, together with the <seed>.bands file can be post-processed with the MolPDOS program with the following command

MolPDOS <seed>

This will write output in the <seed>.castep with following header.

#############################################
#                                           #
#                                           #
#    MolPDOS  -CASTEP Post-processor        #
#                                           #
#       by   R. J. Maurer                   #
#                                           #
#                                           #
#############################################

In addition it will write files for the total DOS (Total-DOS.dat), for the two spin channels if the calculation was spin polarized (Total-DOS_spin1.dat, Total-DOS_spin2.dat), and for the MolPDOS ( <#>_spin<#>_<output_filename).

The keywords for the .molpdos input file can be found below.

Keywords allowed in .molpdos

In the .molpdos files, the keyword title plus colon takes exactly 23 columns (A20,3X). The keyword content starts after that. Lines with # are ignored.

keyword	multiple appearance	arguments and FORTRAN format
molpdos_state	Yes	<# of ref. state I6>1X<spin of ef. state I6>
molpdos_bin_with	No	real number, default=0.01
molpdos_smearing	No	real number, default=0.05
molpdos_scaling	No	real number, default=1.0, scales MolPDOSes
no_fermi_shift	No	no argument, logical, removes fermishift
ax is_energy_margin	No	real in eV default=0.0eV
output_filename	No	<string len=40 filename>

Example .molpdos file:

molpdos_state        :  34     1
molpdos_state        :  35     1
molpdos_state        :  36     1
molpdos_state        :  33     1
molpdos_bin_width    :  0.02
molpdos_smearing     :  0.05
molpdos_scaling      :  1.00
axis_energy_margin   :  2.00
output_filename      :  MolPDOS.dat