[molpro-user] FCI calculation for H3

[Bastiaan J. Braams]

Dear Molpro user,

I would like advice about an FCI calculation for H3.  The following
job fails very quickly with a segmentation fault on my Intel system.

***,SP ENERGY FOR H3 doublet
memory,84,m
geomtyp=xyz
geometry
nosym
  3       h3d.xyz-00000
 -1.670901
H         1.78893575      1.73664337      0.41159189
H         2.32139768      1.27371181      0.47179363
H        -1.87184533     -1.76995798     -0.88345953
end
basis=avtz
rhf;wf,3,1,1
fci
---

(The specific geometry is immaterial.)  Perhaps the system is simply
too large for an FCI calculation, but there is something odd.  If I
change the basis to just vtz then the job runs fine in just a minute
or so.  I would have thought that if an avtz basis for H3 is too
large, then probably H3 on a vtz basis is a very large problem as well
and might take hours.  So I am puzzled that an FCI calculation for H3
using the vtz basis is successful in a minute or so, but the same
calculation on an avtz basis fails.  Any advice?

Bas
--
Bastiaan J. Braams
braams at mathcs.emory.edu
Emory University, Atlanta, GA