The ABINIT Users Mailing List ( CLOSED )

["P. Ganesh" <pganesh@ciw.edu>]

Dear All,

While performing strutural optimization with "optcell 0" and "ionmov 2", 
in the 23d broyden step, in the 6th iteration step number I gett the 
following message:

Min el dens= NaN         el/bohr^3 at reduced coord.  0.9833  0.9815  0.9907
,Max el dens= NaN         el/bohr^3 at reduced coord.  0.0000  0.0000  
0.0000

mkdenpos : WARNING -
 Density went < 0 at    349920 points
 and was set to  1.00E-14.  Lowest was  NaN      .
 Likely due to too low boxcut or too low ecut for pseudopotential core 
charge.
ETOT  6 NaN                   NaN       8.268E-07 NaN       NaN       NaN
scprqt: <Vxc>= -4.0855170E-05 hartree

findmin : WARNING -
 (scfcge) The second derivative is negative, equal to NaN              .
findmin : lambda_predict  NaN         etotal_predict  NaN

scfcge: WARNING -
 Potential-based CG line minimization has trouble to converge.
 The algorithm is restarted with more secure parameters.
scfcge: actual     6-2-1   6.8921E-01 NaN                 NaN
scfcge: predict          NaN          restart the algorithm
scfcge:
scfcge: start      6-3-0   0.0000E+00 NaN                 NaN


Loks like the line minimization is not converging.  I have tried 
increasing the ecut by 30Ha and I get same problem.  Any suggestions 
will be helpful.  My system is an insulator. I am using v5.4.2.

Thanks,
Ganesh