### band structure of Cobalt monolayer

Posted:

**Fri Jun 11, 2021 4:22 am**Dear all;,

I tried to make the band structure of monolayer of Cobalt, but what I get is just flat band ,

I attached the input file and the band structure I got ,

I will be grateful for any feedback or remaks

Thank you very much for your comprehnsion

with nice regards

-------------------

# Crystalline Cobalt 13/06/2020

#

# Computation of the band structure.

# First, a SCF density computation, then a non-SCF band structure calculation.

ndtset 2

#Dataset 1 : usual self-consistent calculation

kptopt1 3 # Option for the automatic generation of k points,

# taking into account the full symmetry

#ngkpt1 4 4 1

prtden1 1 # Print the density, for use by dataset 2

toldfe1 1.0d-12 # This value is way too large for most realistic studies of materials

prtdos2 2

#prtdos1 2

ngkpt1 12 12 1

#Dataset 2 : the band structure

iscf2 -2

getden2 -1

kptopt2 -3 # nb of segments Only 2 segment: G->K and K->M to compare with VASP results

nband2 9

ndivk2 100 70 37 # 10, 12 and 17 divisions of the 2 segments, delimited

# by 3 points.

kptbounds 0 0 0 # Gamma

2/3 -1/3 0 # K

1/2 0 0 # M

0 0 0 # Gamma

tolwfr2 1.0d-12

enunit 1 # Will output the eigenenergies in eV

#Definition of the unit cell

#acell 4.737732368 4.737732368 7.690240466

#angdeg 90 90 120

acell 4.737732368 4.737732368 7.690240466

rprim 0.8660254038E+00 5.0000000000E-01 0.0000000000E+00

-0.8660254038E+00 5.0000000000E-01 0.0000000000E+00

0.0000000000E+00 0.0000000000E+00 1.0000000000E+00

pseudos "Co.GGA_PBE-JTH"

#Definition of the atom types

ntypat 1 # There is one types of atoms

znucl 27 # The keyword "znucl" refers to the atomic number of the

# possible type(s) of atom. The pseudopotential(s)

# mentioned in the "files" file must correspond

# to the type(s) of atom. Here, the only type is Silicon.

#Definition of the atoms

natom 6 # There are three atoms

typat 1 1 1 1 1 1 # They are of type 1 Mo,type 2 sulphur .

#xred # This keyword indicate that the location of the atoms

# 1/3 2/3 1/4

# 2/3 1/3 3/4

#or

xcart

0. 0. 0. #Bohr

4.7377 0 0. #Bohr

0 0. 7.96024 #Bohr

4.7377 0 7.96024 #Bohr

2.36885 4.102968 0. #Bohr

2.36885 4.102968 7.96024 #Bohr

#Definition of the planewave basis set

ecut 20.0 # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure

nstep 50 # Maximal number of SCF cycles

diemac 12.0 # Although this is not mandatory, it is worth to

# precondition the SCF cycle. The model dielectric

# function used as the standard preconditioner

# is described in the "dielng" input variable section.

# Here, we follow the prescription for bulk silicon.

# add to conserve old < 6.7.2 behavior for calculating forces at each SCF step

optforces 1

prtebands 2

prtgeo 2

pawovlp -1

pawecutdg 30

-------------

I tried to make the band structure of monolayer of Cobalt, but what I get is just flat band ,

I attached the input file and the band structure I got ,

I will be grateful for any feedback or remaks

Thank you very much for your comprehnsion

with nice regards

-------------------

# Crystalline Cobalt 13/06/2020

#

# Computation of the band structure.

# First, a SCF density computation, then a non-SCF band structure calculation.

ndtset 2

#Dataset 1 : usual self-consistent calculation

kptopt1 3 # Option for the automatic generation of k points,

# taking into account the full symmetry

#ngkpt1 4 4 1

prtden1 1 # Print the density, for use by dataset 2

toldfe1 1.0d-12 # This value is way too large for most realistic studies of materials

prtdos2 2

#prtdos1 2

ngkpt1 12 12 1

#Dataset 2 : the band structure

iscf2 -2

getden2 -1

kptopt2 -3 # nb of segments Only 2 segment: G->K and K->M to compare with VASP results

nband2 9

ndivk2 100 70 37 # 10, 12 and 17 divisions of the 2 segments, delimited

# by 3 points.

kptbounds 0 0 0 # Gamma

2/3 -1/3 0 # K

1/2 0 0 # M

0 0 0 # Gamma

tolwfr2 1.0d-12

enunit 1 # Will output the eigenenergies in eV

#Definition of the unit cell

#acell 4.737732368 4.737732368 7.690240466

#angdeg 90 90 120

acell 4.737732368 4.737732368 7.690240466

rprim 0.8660254038E+00 5.0000000000E-01 0.0000000000E+00

-0.8660254038E+00 5.0000000000E-01 0.0000000000E+00

0.0000000000E+00 0.0000000000E+00 1.0000000000E+00

pseudos "Co.GGA_PBE-JTH"

#Definition of the atom types

ntypat 1 # There is one types of atoms

znucl 27 # The keyword "znucl" refers to the atomic number of the

# possible type(s) of atom. The pseudopotential(s)

# mentioned in the "files" file must correspond

# to the type(s) of atom. Here, the only type is Silicon.

#Definition of the atoms

natom 6 # There are three atoms

typat 1 1 1 1 1 1 # They are of type 1 Mo,type 2 sulphur .

#xred # This keyword indicate that the location of the atoms

# 1/3 2/3 1/4

# 2/3 1/3 3/4

#or

xcart

0. 0. 0. #Bohr

4.7377 0 0. #Bohr

0 0. 7.96024 #Bohr

4.7377 0 7.96024 #Bohr

2.36885 4.102968 0. #Bohr

2.36885 4.102968 7.96024 #Bohr

#Definition of the planewave basis set

ecut 20.0 # Maximal kinetic energy cut-off, in Hartree

#Definition of the SCF procedure

nstep 50 # Maximal number of SCF cycles

diemac 12.0 # Although this is not mandatory, it is worth to

# precondition the SCF cycle. The model dielectric

# function used as the standard preconditioner

# is described in the "dielng" input variable section.

# Here, we follow the prescription for bulk silicon.

# add to conserve old < 6.7.2 behavior for calculating forces at each SCF step

optforces 1

prtebands 2

prtgeo 2

pawovlp -1

pawecutdg 30

-------------