[molpro-user] Matrix not symmetric in mrcic

[Jacky LIEVIN]

Dear all,

I’m getting the warning "Matrix not symmetric" when running mrcic on a closed shell system using the AVQZ and AV5Z basis sets 

The results seem to be « normal »  in the first iterations (the delta value is small) :
WARNING: Matrix not symmetric
 The problem occurs in CiUtils.cpp:3286
    Mat(iRow,iCol) = 0.206854
    Mat(iCol,iRow) = 0.206854
 delta = 4.10041e-08
 ITER.     SQ.NORM    TOTAL ENERGY    CORR.ENERGY   ENERGY CHANGE      VAR         CPU
   2     1.17174241  -244.98648144    -0.59437726    -0.59437726    5.46e-03     60.11

But rapidly the delta value increases and the results are crazy (very large norm and unrealistic value of the correlation energy)
    Mat(iRow,iCol) = -3.86098
    Mat(iCol,iRow) = -3.86625
 delta = 0.00526768
102698097.32853531  -264.71877855   -20.32667437    -0.04311648    6.81e-05    550.27

What is strange is that the same calculation runs fine with the VnZ basis set series (n= T, Q, 5) and with AVTZ.

Could anyone help me to understand what may happen and suggest me what to do.
Many thanks in advance

Jacky Liévin
Université Libre de Bruxelles

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.molpro.net/pipermail/molpro-user/attachments/20161129/0a1249ae/attachment.html>