[molpro-user] Total energy unreasonable

[Vincent Liégeois]

Dear all


I would like to run a simple test case consisting of a chain of H atoms.

Here is the input file:
***,Hchain
!
memory,400,M
!
GEOMETRY={angstroms,
H1
H2      H1        3.00
H3      H2        3.00    H1    180.000
H4      H3        3.00    H2    180.0000    H1    180.0000
H5      H4        3.00    H3    180.000     H2    180.0000
H6      H5        3.00    H4    180.0000    H3    180.0000
H7      H6        3.00    H5    180.000     H4    180.0000
H8      H7        3.00    H6    180.0000    H5    180.0000
}
!
!
BASIS=3-21G
!
!

GPRINT, BASIS
INT
HF
wf, 8,1,0
orbprint,4,0

___


I have an error message in the scf iterative cycle:

1PROGRAM * RHF-SCF (CLOSED SHELL)       Authors: W. Meyer, H.-J. Werner


  NUMBER OF ELECTRONS:       4+    4-    SPACE SYMMETRY=1    SPIN  
SYMMETRY=Singlet
  CONVERGENCE THRESHOLDS:    1.00E-08 (Density)    1.00E-07 (Energy)
  MAX. NUMBER OF ITERATIONS:       80
  INTERPOLATION TYPE:            NONE
  INTERPOLATION STEPS:              2 (START)      1 (STEP)
  LEVEL SHIFTS:                  0.00 (CLOSED)  0.00 (OPEN)




  Molecular orbital dump at record        2100.2

  ITERATION    DDIFF          GRAD             ENERGY        2- 
EL.EN.            DIPOLE MOMENTS         DIIS
     1      0.000D+00      0.000D+00        -1.46094922      
11.041593   0.000000   0.000000   0.000000    0
     2      0.000D+00      0.541D-01        -1.40980068       
8.817113   0.000000   0.000000   0.000000    0
     3      0.390D+00      0.697D-01        -1.37886802      
11.199517   0.000000   0.000000   0.000000    0
     4      0.395D+00      0.764D-01        -1.37104244       
8.879144   0.000000   0.000000   0.000000    0
     5      0.397D+00      0.761D-01        -1.36517093      
11.223967   0.000000   0.000000   0.000000    0
  ?TOTAL ENERGY UNREASONABLE, ETOT =        -0.13652D+01, ENEST  
=          -0.39200D+01





If i run this calculation in an other program such as gaussian, it  
converged after 6 cycles with this energy:
SCF Done:  E(RHF) =  -3.21537564230     A.U. after    6 cycles
              Convg  =    0.2935D-03             -V/T =  2.0255
              S**2   =   0.0000
  KE= 3.135394836528D+00 PE=-1.200022632354D+01 EE= 3.225320252403D+00



As someone experienced the same problem?
I have try to play on different threshold like twoint or throvl  
without succes.


Thanks in advance

Vincent LIEGEOIS


Dr. Vincent LIEGEOIS
Laboratorium für Physikalische Chemie
ETH, HCI G230
Wolfgang-Pauli-Str. 10
8093 Zürich (Switzerland)
Tel: +41-44-63-22850
Fax: +41-44-63-31594