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I am trying to get the phonon frequencies of an insulator. I am using 10 datasets in the input file. The code does not proceed beyond the ddk calculation. ie dataset3. I get the following error message:

Subroutine Unknown:0:ERROR
The file cg-trf2_1o_DS1_WFK cannot be used to start the
present calculation. It was asked that the wavefunctions be accurate, but
at least one of the k points could not be generated from a symmetrical one.
dksqmax= 1.209678E-03
Action: check your wf file and k point input variables
(e.g. kptopt or shiftk might be wrong in the present dataset or the preparatory one.

Subroutine Unknown:0:ERROR
The file cg-trf2_1o_DS1_WFK cannot be used to start the
present calculation. It was asked that the wavefunctions be accurate, but
at least one of the k points could not be generated from a symmetrical one.
dksqmax= 1.209678E-03
Action: check your wf file and k point input variables
(e.g. kptopt or shiftk might be wrong in the present dataset or the preparatory one.

leave_new : decision taken to exit ...

I have attached the input file:
ndtset 10
#Set 1 : ground state self-consistency

getwfk1 0 # Cancel default
kptopt1 1 # Automatic generation of k points, taking
# into account the symmetry
nqpt1 0 # Cancel default
tolvrs1 1.0d-18 # SCF stopping criterion (modify default)
rfphon1 0 # Cancel default

#Q vectors for all datasets

#Complete set of symmetry-inequivalent qpt chosen to be commensurate
# with kpt mesh so that only one set of GS wave functions is needed.
#Generated automatically by running GS calculation with kptopt=1,
# nshift=0, shiftk=0 0 0 (to include gamma) and taking output kpt set
# file as qpt set. Set nstep=1 so only one iteration runs.

nqpt 1 # One qpt for each dataset (only 0 or 1 allowed)
# This is the default for all datasets and must
# be explicitly turned off for dataset 1.

qpt2 0.00000000E+00 0.00000000E+00 0.00000000E+00
qpt3 0.00000000E+00 0.00000000E+00 0.00000000E+00
qpt4 1.25000000E-01 1.25000000E-01 1.25000000E-01
qpt5 3.75000000E-01 1.25000000E-01 1.25000000E-01
qpt6 -1.25000000E-01 1.25000000E-01 1.25000000E-01
qpt7 -3.75000000E-01 3.75000000E-01 1.25000000E-01
qpt8 -1.25000000E-01 3.75000000E-01 1.25000000E-01
qpt9 -3.75000000E-01 -3.75000000E-01 1.25000000E-01
qpt10 -3.75000000E-01 3.75000000E-01 3.75000000E-01

#Set 2 : Response function calculation of d/dk wave function

iscf2 -3 # Need this non-self-consistent option for d/dk
kptopt2 2 # Modify default to use time-reversal symmetry
rfphon2 0 # Cancel default
rfelfd2 2 # Calculate d/dk wave function only
tolwfr2 1.0d-22 # Use wave function residual criterion instead

#Set 3 : Response function calculation of Q=0 phonons and electric field pert.

getddk3 2 # d/dk wave functions from last dataset
kptopt3 2 # Modify default to use time-reversal symmetry
rfelfd3 3 # Electric-field perturbation response only

#Sets 4-10 : Finite-wave-vector phonon calculations (defaults for all datasets)

getwfk 1 # Use GS wave functions from dataset1
kptopt4 3 # Need full k-point set for finite-Q response
kptopt5 3
kptopt6 3
kptopt7 3
kptopt8 3
kptopt9 3
kptopt10 3
rfphon 1 # Do phonon response
rfatpol 1 4 # Treat displacements of all atoms
rfdir 1 1 1 # Do all directions (symmetry will be used)
tolvrs 1.0d-8 # This default is active for sets 3-10

#######################################################################
#Common input variables

#Definition of the unit cell
acell 3.8037 3.8037 3.8037 angstrom
rprim -0.5000000000000000 0.5000000000000000 0.5000000000000000
0.5000000000000000 -0.5000000000000000 0.5000000000000000
0.5000000000000000 0.5000000000000000 -0.5000000000000000

#Definition of the atom types
ntypat 1 # There are two types of atom
znucl 7.0 # 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.

#Definition of the atoms
natom 4 # There are two atoms
typat 1 1 1 1 # 4 atoms of the same type .


xred 0.17000000000000017 0.1700000000000017 0.1700000000000017
0.5000000000000000 0.0000000000000000 0.3299999999999983
0.0000000000000000 0.3299999999999983 0.5000000000000000
0.3299999999999983 0.5000000000000000 0.0000000000000000


#Gives the number of band, explicitely (do not take the default)
nband 20

#Exchange-correlation functional

ixc 11 # GGA, Perdew-Burke-Ernzerhof GGA functional

#Definition of the planewave basis set

ecut 500 eV # Maximal kinetic energy cut-off, in eV

#Definition of the k-point grid
ngkpt 4 4 4
nshiftk 1 # Use one copy of grid only (default)
shiftk 0.0 0.0 0.0 # This gives the usual fcc Monkhorst-Pack grid
# 0.5 0.5 0.5
# 0.5 0.5 0.5
# 0.5 0.5 0.5

#Definition of the SCF procedure
iscf 5 # Self-consistent calculation, using algorithm 5
nstep 25 # Maximal number of SCF cycles
diemac 1.0d0 # 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.
# add to conserve old < 6.7.2 behavior for calculating forces at each SCF step
optforces 1


Could you please tell me what leads to this error and how I can correct it. Thanks in advance

I ran your input file using the 7n.pspnc pseudopotential from the website, and got the same error. I tracked it down to the fact that the qpt's you are using are not coherent with the kpts you are using. To do self-consistent phonon calculations abinit needs the qpts to be chosen such that they are differences of the kpts used. You get the proper list (the tutorials discuss this) by doing a ground state run with

kptopt 1
nshiftk 1
shiftk 3*0
ngkpt <whatever you are using>

then, take the kpts used (they are listed in the output file) as the qpts for your phonon calc. I did this in your input file and it runs fine.

Thank you Professor. But I did that step and the code generates this message before completing DATASET3 calculations:

==> Compute Derivative Database <==
dyout3 : exit

phonon wavelength (reduced coordinates) , norm, and energies in hartree
0.00 0.00 0.00 1.00
6.321301927E-03 6.321528599E-03 6.321844904E-03 7.052112004E-03 7.052307063E-03
7.580224962E-03 7.717861425E-03 7.717929610E-03 7.718146785E-03 7.869545599E-03
7.869649589E-03 7.869741256E-03
Zero Point Motion energy (sum of freqs/2)= 4.370609686E-02
.......................

Subroutine Unknown:0:ERROR
fxphas_seq:
The eigenvector number1 has zero norm.

Subroutine Unknown:0:ERROR
fxphas_seq:
The eigenvector number1 has zero norm.

leave_new : decision taken to exit ...

Sorry.. but something is still wrong...

Sorry.. Professor, the code runs fine with your suggestion. I had made a typo in my input file.

Thanks a lot..
Uma

Many thanks.
Uma