nband in input file and pspatm in log file
Posted: Fri May 06, 2011 6:12 pm
Hello:
I am new to ABINIT and I have some questions about the input and output files. Problem: I have the phase Ti5Pt3 (16 atoms, hexagonal, P63/mcm) and I want to obtain the best cut-off energy and k-grid (dataset) so then I will use this values to expand the crystal structure to 80 atoms (new phase). Here, I am assuming that these values will be good for this new crystal structure. I run the dataset for 4x4x4 and I varied the ecut from [4:2:20], but at ecut=10 and above the output file said something about the k-points and that I should increase the number of band (before that I let the software to calculate the best nband for Ti and Pt and it was 58). So, I increased to 60. Then at ecut=16, the same thing happened and I increased the nband to 62. How can I approach (solve) this issue?
Second, a paragraph in the log file said:
Is this important? is there something that I need to change in the input file? Mi input file is:>
I hope somebody in this forum can help me.
Best Regards,
Karem
I am new to ABINIT and I have some questions about the input and output files. Problem: I have the phase Ti5Pt3 (16 atoms, hexagonal, P63/mcm) and I want to obtain the best cut-off energy and k-grid (dataset) so then I will use this values to expand the crystal structure to 80 atoms (new phase). Here, I am assuming that these values will be good for this new crystal structure. I run the dataset for 4x4x4 and I varied the ecut from [4:2:20], but at ecut=10 and above the output file said something about the k-points and that I should increase the number of band (before that I let the software to calculate the best nband for Ti and Pt and it was 58). So, I increased to 60. Then at ecut=16, the same thing happened and I increased the nband to 62. How can I approach (solve) this issue?
Second, a paragraph in the log file said:
Code: Select all
pspatm : COMMENT -
the projectors are not normalized,
so that the KB energies are not consistent with
definition in PRB44, 8503 (1991).
However, this does not influence the results obtained hereafter.
pspatm: epsatm= 13.02881305
Is this important? is there something that I need to change in the input file? Mi input file is:>
Code: Select all
# Ti5Pt3
#ndtset 9
#ecut: 4 ecut+ 2
getwfk -1 # This is to speed up the calculation, by restarting
# from previous wavefunctions, transferred from the old
# to the new k-points.
#Definition of occupation numbers
occopt 4 #metallic occupation of levels. Cold smearing of N. Marzari
tsmear 0.05 #broadening of the occupation numbers
#Definition of the unit cell
acell 15.1178 15.1178 9.4486 # hexagonal
rprim 1.0 0.0 0.0 #hexagonal primitive vectors must be
-0.5 0.866025403784439 0.0 #specified with high accuracy to be
0.0 0.0 1.0 #sure that the symmetry is recognized
#and preserved in the optimization
#process
#Definition of the atom types
npsp 2 # 2 pseudopotentials
ntypat 2 # 2 type of atoms
znucl 22 78 # 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.
nband 62
#Definition of the atoms
natom 16 # 16 atoms
typat 10*1 6*2
xred 0.33333333 0.66666667 0.00000000 #Ti1
0.66666667 0.33333333 0.50000000 #Ti2
0.66666667 0.33333333 0.00000000 #Ti3
0.33333333 0.66666667 0.50000000 #Ti4
0.23600000 0.00000000 0.25000000 #Ti5
-0.23600000 0.00000000 0.75000000 #Ti6
0.00000000 0.23600000 0.25000000 #Ti7
0.00000000 -0.23600000 0.75000000 #Ti8
0.23600000 0.23600000 0.75000000 #Ti9
-0.23600000 -0.23600000 0.25000000 #Ti10
0.59950000 0.00000000 0.25000000 #Pt1
-0.59950000 0.00000000 0.75000000 #Pt2
0.00000000 0.59950000 0.25000000 #Pt3
0.00000000 -0.59950000 0.75000000 #Pt4
0.59950000 0.59950000 0.75000000 #Pt5
-0.59950000 -0.59950000 0.25000000 #Pt6
#Definition of the k-point grid
ngkpt 4 4 4 # Definition of the different grids
nshiftk 1 # of the reciprocal space. For a hcp
shiftk 0.0 0.0 0.5
#Exchange-correlation functional
ixc 1 # LDA Teter Pade parametrization
#Definition of the planewave basis set
ecut 18.0 # Maximal kinetic energy cut-off, in Hartree
#Definition of the SCF procedure
nstep 70 # Maximal number of SCF cycles
toldfe 1.0d-6 # Will stop when, twice in a row, the difference
# between two consecutive evaluations of total energy
# differ by less than toldfe (in Hartree)
# This value is way too large for most realistic studies of materials
I hope somebody in this forum can help me.
Best Regards,
Karem