[molpro-user] Density Fitting

[Glen Jenness]

Dear Molpro users,
I’m currently using the density fitting DFT-SAPT module in 2006v.1 of Molpro.
I did a AVTZ (with VQZ and AVTZ as my coulomb (exchange) and MP2 aux.
basis) with benzene-water.  When I did this, I noticed the following
message in the benzene part of the calculation (it appears before the
first iteration):

NO CONVERGENCE in PIPEKS AFTER MAX ITERATIONS. LARGEST ROTATION ANGLE=
0.00008498

The run will complete, but I get nonsensical results for the interaction
energy and components.  This problem also appears when I use the AVDZ
basis (with VTZ and AVDZ aux.) with density fitting.
However, this problem doesn't exist with AVDZ and VTZ (I haven't done AVTZ
due to hard disk restrictions) without density fitting.
I also have a second problem with AVTZ with density fitting (that's prob.
due to a bad input, but I can't figure it out).  For some reason, it seems
to act like density fitting isn't there with respect to disk space
savings.  I did coronene-water with density fitting, and the disk used was
~30GB, so for bezene water (with fewer functions) should take less disk
space, but this isn't happening.
If anyone can shed any light on either one of these, it would be greatly
appreciated.  I've included the full outputs from both density fitting
benzene-water runs.
Thanks,
Glen Jenness
Jordan Group
Department of Chemistry
University of Pittsburgh