[molpro-user] multiple core specifications in one input

[Kirk Peterson]

Brian,

I've also reproduced this.  This does not occur with the 2002.9 
development version and I think the
problem is that the integral transformation is not carried out in the 
3rd ccsd(t) and the operators
are re-used from the core,0 calculation (as noted in the output) .  It 
looks like the program has no problem if the number of
core orbitals just decreases in subsequent calls, e.g., core,2 then 
core,1 and then core,0.  It doesn't
seem to expect the number of cores to go back and forth.  A quick hack 
is to redo the rhf step before the 3rd ccsd(t)
calculation.

-Kirk

On Aug 10, 2005, at 12:56 PM, Brian wrote:

> If you try something along the lines of
>  
> hf
> ccsd(t)
> core,1
> ccsd(t)
> core,0
> ccsd(t)
> core,1
>  
> for water, you will find that the first and last ccsd(t) values are 
> different.  In fact, the second enery is lower than the correct 
> energy.  Is this a known bug?
>  
> -Brian