MRCI: restart and one-interaction only

[Julien Toulouse]

Dear Molpro developers and users,

I would like to compute the expectation value <Psi' | H | Psi' > where 
|Psi'> is the  multi-determinantal ground-state wave function computed 
in a previous MRCI with a different Hamiltonian H'.

Is it possible to use the MRCI program with the "start" card to recover 
the previously saved wave function |Psi'> and to perform only one 
iteraction in order to compute
 <Psi' | H | Psi' > ?

So far, all the tests I have done failed.

For example, in the following simple input where H=H', the second 
one-iteraction only MRCI does not give the right energy <Psi' | H | Psi' 
 > . It seems that the wave function |Psi'> is not properly recovered by 
the "start" keyword.

Does anyone know how to proceed?


Best regards,

Julien Toulouse
Laboratoire de Chimie Theorique
Paris

----------------------
***, He

geom={He}

basis=vtz

hf;
   occ,1
   wf,2,1,0;

! First MRCI to calculate Psi'
ci
   occ,3,2,2,,2
   closed
   core
   wf,2,1,0;
   save,2341.3,2342.3,1;  ! save wave function Psi'
 
! Second MRCI to calculate <Psi'|H|Psi'>
ci
 start,2341.3,1                        ! starting wave function Psi'
 option,maxiti=1,maxit=1  ! no iteration, compute only <Psi'|H|Psi'>