[CPMD-list] question about the optimalization of cell parameter

[Bako Imre]

Dear All
I tried to optimize the Si lattize use the following input file
&CPMD
OPTIMIZE GEOMETRY
RESTART WAVEFUNCTION COORDINATES LATEST
SPLINE POINTS
  5000
CONVERGENCE CELL
0.1
&END
&DFT
FUNCTIONAL PZ
&END
 &SYSTEM
SYMMETRY
  2
  CELL
 10.2612 1.0 1.0 0.0 0.0 0.0
   CUTOFF
   36.
KPOINTS MONKHORST-PACK
 4 4 4
STATES
4
POINT GROUP
  AUTO
TESR
  4 4 4
SCALED
 &END
&ATOMS
*Si_SG_LDA KLEINMAN-BYLANDER
  LMAX=D
   2
   0.00  0.00  0.00
   0.25  0.25  0.25
&END
After the second iteration I got the following answer
ATOM          COORDINATES                GRADIENTS
   1 Si  0.0000  0.0000  0.0000   0.000E+00  0.000E+00  0.000E+00
   2 Si -2.5653  2.5653  2.5653   0.000E+00  0.000E+00  0.000E+00
 ****************************************************************
 *** TOTAL STEP NR.     2           GEOMETRY STEP NR.      1  ***
 *** GNMAX=  0.000000E+00                ETOT=     -7.923217  ***
 *** GNORM=  0.000000E+00               DETOT=     0.000E+00  ***
 *** CNSTR=  0.000000E+00                TCPU=          0.73  ***
 ****************************************************************
 ================================================================
 =              END OF GEOMETRY OPTIMIZATION                    =
 ================================================================
Can you explain somebody me this behaviour?
Best regards
Imre Bako

Bakó Imre
MTA Kémiai Kutatóközpont, Kémiai Intézet
1525 Budapest Pf. 17
Telefon