[molpro-user] ? The problem occurs in muwvfc:spieig

[Amar Dora]

Dear Molpro Experts,

I am trying to calculate the potential energy curves of carbon
monoxide molecule at the CASSCF level using the Molpro program Multi.
However, the job crashes time to time in Multi with following error
message :


ITER. MIC  NCI  NEG     ENERGY(VAR)     ENERGY(PROJ)   ENERGY CHANGE
  GRAD(0)  GRAD(ORB)   GRAD(CI)     STEP       TIME

 ms2, ndet, nfns, ntake                      0                     6
                     2                     1
 ? Error
 ? Failure to find complete spin space
 ? The problem occurs in muwvfc:spieig

When resubmitting the job at the crashed geometry it works
successfully but it converges to different states and the potential
curves look discontinuous. My objective is to get the state-averaged
natural MOs of CO at different geometries which will be used further
in R-matrix calculations.


My input for CASSCF is as follows :

############

  {hf;
   orbprint,-1
   orbital,2100.2;
  }


!CAS(10,11): Core = (1 A1 - 2 A1)^4, active (3A1 - 7A1, 1B1 - 3B1, 1B2 - 3B2)^10
{casscf
occ,7,3,3,0;
frozen,2,0,0,0,2100.2;
maxiter,40;
pspace,0.90;
WF,14,1,0; state,4;lquant,0,0,0,0;  !1Sigma+
WF,14,4,0; state,2;lquant,0,0;      !1Sigma-
WF,14,2,0; state,5;lquant,1,1,1,1,1; !1Pi
WF,14,3,0; state,5;lquant,1,1,1,1,1; !1Pi
WF,14,1,0; state,2;lquant,2,2;  !1Delta
WF,14,4,0; state,2;lquant,2,2;  !1Delta
WF,14,1,2; state,4;lquant,0,0,0,0;  !3Sigma+
WF,14,4,2; state,3;lquant,0,0,0;      !3Sigma-
WF,14,2,2; state,5;lquant,1,1,1,1,1; !3Pi
WF,14,3,2; state,5;lquant,1,1,1,1,1; !3Pi
WF,14,1,2; state,2;lquant,2,2;  !3Delta
WF,14,4,2; state,2;lquant,2,2;  !3Delta
orbprint,300
!orbital,ignore_error=1;
}
###########

Thanks for any help!
Amar

-- 
Dr. Amar Dora
Assistant Professor
Department of Chemistry
North Orissa University
Mayurbhanj, Odisha
India