#Test of silicon crystal : RF
#GGA functional
#Note that the number of k points is much too small
#to obtain correct electric field responses
#One should use at least ngkpt 3*4
ndtset 5
#First dataset : SC run with 2 kpoints
#Second dataset : d/dk response calculation
iscf2 -3 rfelfd2 2 getwfk2 1 getden2 1
getddk2 2
rfdir2 1 0 0
kptopt2 2
#Third dataset : phonons and homogeneous electric field response
rfelfd3 3
getwfk3 1
getddk3 2
rfdir3 1 1 1
rfphon3 1
rfatpol3 1 2
tolwfr3 1.0d-12
kptopt3 2
#Fifth and sixth datasets : Finite-differences
xred4 3*0.0d0 3*0.2501d0 getwfk4 1
xred5 3*0.0d0 3*0.2499d0 getwfk5 1
chksymbreak 0
#Common data
acell 3*10.26
ecut 6.00
ixc 11
ngkpt 3*2
natom 2
nband 4
nshiftk 4
nstep 30
ntypat 1
occopt 1
prtden 1
rprim 0.0 0.5 0.5
0.5 0.0 0.5
0.5 0.5 0.0
shiftk 0.5 0.5 0.5
0.5 0.0 0.0
0.0 0.5 0.0
0.0 0.0 0.5
xred 3*0.00d0 3*0.25d0
typat 1 1
tolwfr 1.e-28
znucl 14
#%%
#%% [setup]
#%% executable = abinit
#%% [files]
#%% files_to_test =
#%% t16.out, tolnlines = 0, tolabs = 1.100e-07, tolrel = 4.000e-04, fld_options = -medium
#%% psp_files = 14si.pspnc
#%% [paral_info]
#%% max_nprocs = 2
#%% [extra_info]
#%% authors = Unknown
#%% keywords = NC, DFPT
#%% description =
#%% Si crystal. GGA + non-linear XC core correction.
#%% Compute the interatomic force constant for the displacement of the second atom along (111).
#%% RF calculation of the 2DTE gives 7.51663417 Ha
#%% while finite differences gives: with delta(xred)=0.0001, 7.15663267 Ha.
#%% The agreement is quite good, and might likely be improved by combining finite differences.
#%% Also compute the ddk and electric field responses. The number of k points is much too small to
#%% obtain physical values, but are quite comparable to the result of test v2 #6
#%%