[molpro-user] Another error in MRCI.

[Wang Mingwei]

Hello,

I do series of MRCI calculation for BrCl of given internuclear separations
between 1.6 and 6.0 Å.
When the separation is smaller than 2.2 Å the following same errors occur:
 Number of core orbitals:          14 (   8   3   3   0 )
 Number of closed-shell orbitals:   5 (   2   1   1   1 )
 Number of active  orbitals:        8 (   4   2   2   0 )
 Number of external orbitals:     150 (  56  36  36  22 )

 Molecular orbitals read from record     2140.2  Type=MCSCF/NATURAL (state
averaged)

 Coulomb and exchange operators available. No transformation done.

 Number of p-space configurations:   6
 Removal of internal vectors e(1)<  0.1000000E-14
 e(1).le.1.d-15  -0.4701101E-15
 Catastrophic failure in diagonalization(hsdel)
 The expansion set has become singular
 This difficulty can arise for many reasons
 Sometimes it helps to redefine P space
 Otherwise, try increasing or decreasing reference space or nstati

 ERROR EXIT
 CURRENT STACK:      CIPRO  MAIN
But when the distance is larger than 2.2 Å, MRCI convergence normally.
So, what is reason?
The following is the input file:
***BrCl***
memory,90,m
gprint,orbital,basis
geometry={angstrom;
          BR;
          CL,BR,2.15;}
basis={spdfg,BR,cc-pVQZ-DK;c;
s,BR,0.442700000E-01;
p,BR,0.305130000E-01;
d,BR,0.829000000E-01;
f,BR,0.174800000E+00;
g,BR,0.311000000E+00;
spdfg,CL,cc-pVQZ-DK;c;
s,CL,0.519000000E-01;
p,CL,0.376000000E-01;
d,CL,0.952000000E-01;
f,CL,0.217000000E+00;
g,CL,0.378000000E+00;}

dkroll=1;
hf;
occ,13,6,6,1;wf,52,1,0;

multi;occ,14,6,6,1;core,8,3,3;closed,10,4,4,1;
wf,52,1,0;state,3;wf,52,1,2;state,3;wf,52,2,0;state,2;wf,52,2,2;state,2;
wf,52,3,0;state,2;wf,52,3,2;state,2;wf,52,4,0;state,2;wf,52,4,2;state,3;

mrci;occ,14,6,6,1;core,8,3,3;closed,10,4,4,1;wf,52,1,0;
option,nstati=6;state,3;
e_10(1)=energd(1)
e_10(2)=energd(2)
e_10(3)=energd(3)
mrci;occ,14,6,6,1;core,8,3,3;closed,10,4,4,1;wf,52,1,2;
option,nstati=6;state,3;
e_12(1)=energd(1)
e_12(2)=energd(2)
e_12(3)=energd(3)

mrci;occ,14,6,6,1;core,8,3,3;closed,10,4,4,1;wf,52,2,0;
option,nstati=4;state,2;
e_20(1)=energd(1)
e_20(2)=energd(2)

mrci;occ,14,6,6,1;core,8,3,3;closed,10,4,4,1;wf,52,2,2;
option,nstati=4;state,2;
e_22(1)=energd(1)
e_22(2)=energd(2)

mrci;occ,14,6,6,1;core,8,3,3;closed,10,4,4,1;wf,52,4,0;
option,nstati=4;state,2;
e_40(1)=energd(1)
e_40(2)=energd(2)

mrci;occ,14,6,6,1;core,8,3,3;closed,10,4,4,1;wf,52,4,2;
option,nstati=6;state,3;
e_42(1)=energd(1)
e_42(2)=energd(2)
e_42(3)=energd(3)

table,e_10;digits,8;
table,e_12;digits,8;
table,e_20;digits,8;
table,e_22;digits,8;
table,e_40;digits,8;
table,e_42;digits,8;
In addition, in this work the basis set cc-pvqz-dk is used and one more
diffusion function is added to s,p,d,f,g respectively.
However, I have suceeded  to do such similar a series of calculation using
one smaller cc-pvtz-dk basis set.
So, does the error be  involved in the size of basis set?

Thanks a lot.
mingwei
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://www.molpro.net/pipermail/molpro-user/attachments/20060912/75618433/attachment.html>