[molpro-user] Energy in MRCI-F12 calculation

[Somnath BHOWMICK]

Dear Molpro Users,

I think I have solve the problem. The difference in energy is indeed "CABS singles correction" included in energy variables, as Kirk mentioned previously. One can verify this by putting SINGLES=0 in the command line, which disables the singles correction, then no difference in energies are obtained.

Best regards.
Somnath 

> ----------------------------------------
> From: Peterson, Kirk <kipeters at wsu.edu>
> Sent: Wed Jul 16 21:11:56 CEST 2014
> To: Somnath BHOWMICK <somnath.bhowmick at etu.univ-amu.fr>
> Subject: Re: [molpro-user] Energy in MRCI-F12 calculation
> 
> 
> Dear Somnath,
> 
> I think the issue is that the energies saved in the energy and energd variables include the CABS singles correction.  At least with the developer's version (sorry, I don't have the production version currently built), the energies saved are consistent with adding about -0.007 Eh to the energies printed out after the main CI iterations.
> 
> -Kirk
> 
> On Jul 16, 2014, at 11:33 AM, Somnath BHOWMICK <somnath.bhowmick at etu.univ-amu.fr> wrote:
> 
> > Dear Kirk,
> > 
> > When I use MRCI-F12a in the command line, I am getting the error:
> > 
> > Checking input...
> > 
> > Unknown directive MRCI-F12A for command MCSCF
> > 
> > GLOBAL ERROR checkinp on processor   0
> > 
> > When I use MRCI-F12b in the command line, I can calculate the states. However, there still remains the energy difference as mentioned in the previous mail.
> > 
> > Somnath
> > 
> >> ----------------------------------------
> >> From: Peterson, Kirk <kipeters at wsu.edu>
> >> Sent: Wed Jul 16 19:34:01 CEST 2014
> >> To: Somnath BHOWMICK <somnath.bhowmick at etu.univ-amu.fr>
> >> Subject: Re: [molpro-user] Energy in MRCI-F12 calculation
> >> 
> >> 
> >> Dear Somnath,
> >> 
> >> when you specify MRCI-F12 or CCSD-F12, etc,  without any specification of F12a or F12b, both methods are actually computed and the F12a energy is stored in energy(1) and F12b into energy(2) (analogously with energd).  I'm not sure how this is handled in MRCI-F12 when you ask for more than 1 root, but perhaps chaos.  If you really want just F12a, then use   MRCI-F12a on your command line and then all should be as expected.
> >> 
> >> regards,
> >> 
> >> -Kirk
> >> 
> >> 
> >> On Jul 16, 2014, at 10:26 AM, Somnath BHOWMICK <somnath.bhowmick at etu.univ-amu.fr> wrote:
> >> 
> >>> Dear Kirk,
> >>> 
> >>> Thanks for the prompt response. Please find a sample output with this mail. I am getting two different energy values MRCI-F12, when I tabulate it. For, example: for state 1.1, 
> >>> 
> >>> !CI-F12 STATE 1.1 Energy            -114.538939848235
> >>> Cluster corrected energies          -114.55264645 (Davidson, relaxed reference)
> >>> 
> >>> However, in the table:
> >>> 
> >>> energy(1)=-114.5459572
> >>> energd(1)=-114.5596638
> >>> 
> >>> Thanks.
> >>> Somnath
> >>> 
> >>> 
> >>> 
> >>>> ----------------------------------------
> >>>> From: Peterson, Kirk <kipeters at wsu.edu>
> >>>> Sent: Wed Jul 16 18:03:36 CEST 2014
> >>>> To: Somnath BHOWMICK <somnath.bhowmick at etu.univ-amu.fr>
> >>>> Subject: Re: [molpro-user] Energy in MRCI-F12 calculation
> >>>> 
> >>>> 
> >>>> Dear Somnath,
> >>>> 
> >>>> can you send your full input or output to the list?  Otherwise it is pretty difficult to guess what is going on.
> >>>> 
> >>>> thanks,
> >>>> 
> >>>> -Kirk
> >>>> 
> >>>> On Jul 15, 2014, at 10:12 AM, Somnath BHOWMICK <somnath.bhowmick at etu.univ-amu.fr> wrote:
> >>>> 
> >>>>> Dear Molpro users,
> >>>>> 
> >>>>> I am trying to calculate PEC of a triatomic system in MRCI-F12A. However, I am really having trouble correctly define the total energy of the system. For example: the energy mentioned in the block where it specifies the energy of a particular state, just like "!CI-F12 STATE 1.1 Energy" value is different than if I tabulate it as ENERGY(1).  Similar contrasting values are obtained if I want to tabulate the Davidson corrected values as ENERGD(1).
> >>>>> 
> >>>>> Thanks in advance.
> >>>>> 
> >>>>> 
> >>>>> With very best of regards
> >>>>> Somnath Bhowmick
> >>>>> 
> >>>>> Equipe de Chimie Théorique et Modélisation (CTOM)
> >>>>> Institut des Sciences Moléculaires de Marseille (iSm2)
> >>>>> UMR CNRS 7313,
> >>>>> Université d'Aix-Marseille
> >>>>> UPCAM iSm2 Service 561
> >>>>> Campus Scientifique de St Jérôme
> >>>>> 13397 Marseille cedex 20
> >>>>> France
> >>>>> 
> >>>>> _______________________________________________
> >>>>> Molpro-user mailing list
> >>>>> Molpro-user at molpro.net
> >>>>> http://www.molpro.net/mailman/listinfo/molpro-user
> >>>> 
> >>> 
> >>> 
> >>> With very best of regards
> >>> Somnath Bhowmick
> >>> 
> >>> Equipe de Chimie Théorique et Modélisation (CTOM)
> >>> Institut des Sciences Moléculaires de Marseille (iSm2)
> >>> UMR CNRS 7313,
> >>> Université d'Aix-Marseille
> >>> UPCAM iSm2 Service 561
> >>> Campus Scientifique de St Jérôme
> >>> 13397 Marseille cedex 20
> >>> France
> >>> http://ism2.univ-amu.fr/equipes/CTOM_1.htm<test.out>
> >> 
> > 
> > 
> > With very best of regards
> > Somnath Bhowmick
> > 
> > Equipe de Chimie Théorique et Modélisation (CTOM)
> > Institut des Sciences Moléculaires de Marseille (iSm2)
> > UMR CNRS 7313,
> > Université d'Aix-Marseille
> > UPCAM iSm2 Service 561
> > Campus Scientifique de St Jérôme
> > 13397 Marseille cedex 20
> > France
> > http://ism2.univ-amu.fr/equipes/CTOM_1.htm
> 


With very best of regards
Somnath Bhowmick

Equipe de Chimie Théorique et Modélisation (CTOM)
Institut des Sciences Moléculaires de Marseille (iSm2)
UMR CNRS 7313,
Université d'Aix-Marseille
UPCAM iSm2 Service 561
Campus Scientifique de St Jérôme
13397 Marseille cedex 20
France
http://ism2.univ-amu.fr/equipes/CTOM_1.htm