How to calculate and plot the substates eg and t2g of the d state of atom Ti in TiC

In the previous tutorial (How to calculate the Partial and Total DOS of Titanium Carbide ) we have plotted the s,p and d states of atoms Ti and C in Titanium Carbide. Today we will present how to split the d state of atom Ti into substates eg and t2g.

We need the input file 

 

elk.in

! Density of states of TiC resolved into irreducible representations. When
! lmirep is set to .true., the Y_lm basis is transformed into one in which the
! site symmetries are block diagonal. The band characters determined from the
! density matrix expressed in this basis correspond therefore to irreducible
! representations (IR).

! In this example, we want the e_g and t_2g resolved DOS for the Ti atom. The
! ELMIREP.OUT file contains a set of eigenvalues, the degeneracies of which
! allow for easy identification of the IR. For l = 2, the 3-fold degeneracy is
! the t_2g IR, while the 2-fold is the e_g IR. Adding together curves 5, 6 and 7
! in the file PDOS_S01_A0001.OUT will give the t_2g plot, and adding curves 8
! and 9 will give the e_g plot.

tasks
  0
  10

lmirep
  .true.

avec
  0.5  0.5  0.0
  0.5  0.0  0.5
  0.0  0.5  0.5

scale
  8.1787

sppath
  '/home/algerien/abinitio/elk-3.3.17/species/'

atoms
  2                                 : nspecies
  'Ti.in'                           : spfname
  1                                 : natoms; atposl below
  0.0  0.0  0.0
  'C.in'
  1
  0.5  0.5  0.5

ngridk
  8  8  8

This option allows to split the p, d and f states into 3, 5 and 7 orbitals, respectively.

lmirep
  .true.

 

Note: Don't forget to ajust the species path according to your case

'/home/algerien1970/abinitio/elk-3.3.17/species/'

 

 

Calculation

algerien1970@linux-ml0a:~/abinitio/elk-tutorials/TiC-eg-t2g> elk

algerien1970@linux-ml0a:~/abinitio/elk-tutorials/TiC_PDOS> xmgrace PDOS_S01_A0001.OUT

 

The output file PDOS_S01_A0001.OUT  contains now 16 blocks configured as follows:

l = 0, m = 0
l = 1, m = -1
l = 1, m= 0
l = 1, m = +1
l = 2, m = -2
l = 2, m = -1
l = 2, m = 0
l = 2, m = +1
l = 2, m = +2
l = 3, m = ...

Ref: https://elk-algerien1970.blogspot.com/p/pdosout-explanation.html

NB:

Adding together curves 5, 6 and 7 in the file PDOS_S01_A0001.OUT will give the t_2g plot, 

and adding curves 8 and 9 will give the e_g plot.

To do that check this link: https://stackoverflow.com/questions/41962443/add-data-sets-with-xmgrace