The ABINIT Users Mailing List ( CLOSED )

[smidstrup@math.aau.dk]

Dear Abinit users.

I am currently working on calculating the frequency dependent 
dielectric-constant for wurtzite ZnO. I am using the test_v4 - t56.in and 
t57.in as guidelines.
And I use the optic code - ( which I compiled some days ago with help from 
this forum. thx ).
However I seems have to a problems

At first let me say that i works with few k-points like around 800 kpoints, 
and it gives decent looking dielectric-constant.
When I increase the number of kpoints, then wavefunction files on the disc go 
crazy. 1500 kpoint result in a WFK file for a extreme size of 3.3 GB !!!
And for 3500 kpoint the WFK files is abourt 6.7 GB.

As one could expect, when trying to use the optic code on these WFK files, it 
results in severe fortran error : (30) - File to Large.

So If any have some thoughts on how one could deal with this problem, it 
would be a great help.

Alternative it could also help if some knew who to print matrix elements of 
momenentum operator express in the basis set, then I could code my own 
program for calculating the frequency dependent dieelectric constant.

With the best regards:
 Søren Smidstrup
 Aalborg Universitet
 Denmark

P.S
I use mkmem and mkqmem to keep Abinit from failing. I am currently working on 
a 2 GB memory machine, but with some many kpoints these settings keep the 
computer from running out of memory.



ndtset 5

# Ground State Calculateion

prtden1 1    # Dump the n(r)
getden1 0    # Dont read - but calculate n(r)
getwfk1 0    # Dont read - but calculate psi(r)
iscf1 5      # Self-consistent-calculation

# More K-points for the Ground State

iscf2 -2
getwfk2 1
getden2 1


# ddk response function for E_x
iscf3 -3               # Non-Self-consistent-calculation.
getwfk3 2              # Get the wavefunction from dataset 1
nqpt3 1                # Number of wavevectors of perturbation.
qpt3 0.0d0 0.0d0 0.0d0 # Wavevector of perturbation.
rfelfd3 2              # Perturbation of electric type.
rfdir3 1 0 0           # E = (x,0,0)


# ddk response function for E_y
iscf4 -3
getwfk4 2
nqpt4 1
qpt4 0.0d0 0.0d0 0.0d0
rfelfd4 2
rfdir4 0 1 0


# ddk response function for E_z
iscf5 -3
getwfk5 2
nqpt5 1
qpt5 0.0d0 0.0d0 0.0d0
rfelfd5 2
rfdir5 0 0 1


# Common Settings.

acell  3.19200 3.19200 5.18500 angstrom
angdeg 90 90 120

# Definitions of atoms.
   ntypat 2
   zatnum 30 8
   natom 4
   typat 1 1 2 2 

# Definition of Exchange/Corr. function  # 1 = LDA, 11 = GGA,PBE
   ixc 1


# Postion of the atoms.
  xred
   0.33333333333333333    0.66666666666666666    0.0000000000000
   0.66666666666666666    0.33333333333333333    0.5000000000000
   0.33333333333333333    0.66666666666666666    0.3759563334981
   0.66666666666666666    0.33333333333333333    0.8759563334981

# Cutoff energy for  plane wave basis set.
   ecut 45

# Limits for SFC.
   nstep 70
   diemac 12.0


   kptopt 1
   iscf 5
   tolwfr1 1.0d-18
   tolwfr2 1.0d-18
   tolvrs3 1.0d-10
   tolvrs4 1.0d-10
   tolvrs5 1.0d-10
   ngkpt1 8 8 4     #20 20 10
   ngkpt2 40 40 20
   ngkpt3 40 40 20
   ngkpt4 40 40 20 
   ngkpt5 40 40 20
   nshiftk 1
   shiftk  0.0  0.0  0.5
   nband 30
   prtvol 3
   mk1mem 220
   mkmem 220
   mkqmem 220