# MgAl2 with CdI2 structure - to test metallic Q=0 0 0 phonons
# verifies that 1st-order Fermi energy is functioning properly
ndtset 3
# Set 1 : initial self-consistency
#irdwfk1 1
kptopt1 1
prtden1 1
tolvrs1 1.0d-10
# Set 2 : wavefunction convergence
getden2 -1
getwfk2 -1
iscf2 -2
kptopt2 1
tolwfr2 1.0d-10
# Set 3 : response-function phonon calculation
getwfk3 -1
kptopt3 2
nqpt3 1
qpt3 0 0 0
rfatpol3 2 2
rfdir3 0 0 1
rfphon3 1
tolvrs3 1.0d-8
# common input data
acell 5.581 5.581 13.180
angdeg 90.0 90.0 120.0
ecut 5.0
natom 3
nband 8
ngkpt 6 6 4
nshiftk 1
nstep 50
ntypat 2
occopt 3
shiftk 0.0 0.0 0.5
tsmear 0.003
typat 1 2 2
xred 0.0 0.0 0.0
1/3 2/3 0.3433
2/3 1/3 -0.3433
znucl 12 13
#%%
#%% [setup]
#%% executable = abinit
#%% [files]
#%% files_to_test =
#%% t60.out, tolnlines = 1, tolabs = 4.000e-08, tolrel = 4.000e-04, fld_options = -medium
#%% psp_files = 12mg.pspnc, 13al.pspnc
#%% [paral_info]
#%% max_nprocs = 10
#%% [extra_info]
#%% authors = D. R. Hamann
#%% keywords = NC, DFPT
#%% description =
#%% Test of the the effect of the first-order Fermi energy on a Q=0
#%% phonon calculation in metals.
#%% The example is for a hypothetical intermetallic compound MgAl2,
#%% in a structure which can be thought of as fcc Al with every third
#%% (111) layer replaced by Mg. Technically, this is the hexagonal
#%% CdI2 structure, space group #164, P-3 m 1. For this case, neglect
#%% of this contribution yields approximately a 2% error in the largest
#%% interatomic force constants. Its effect on many force constants
#%% for this system cancels because of symmetry. This calculation
#%% is not particularly well converged, especially with respect
#%% to k sample. A well-converged version is in excellent agreement
#%% with interatomic force constants calculated by numerical
#%% differentiation of ground-state forces.
#%%