[molpro-user] ZPE is = 0.00000. Is it Correct?

[Mariusz Radon]

> Date: Thu, 29 Jun 2017 10:57:25 +0300
> From: David Danovich <david.danovich at gmail.com>
> To: molpro-user at molpro.net
> Subject: [molpro-user] ZPE is = 0.00000. Is it Correct?
> Message-ID:
> 	<CACSY2O6JO=Es=H=XGowR4uzWzqxw=YEx3v_KDh0iP5NBYDFQwQ at mail.gmail.com>
> Content-Type: text/plain; charset="utf-8"
> 
> Hello,
> 
> I have done freq calculation with following input. Freq calculation seems
> to be correct. It is TS with one imaginary freq but ZPE correction equals
> exact 0.0000000. Is it correct?
> 

Dear David,
judging from the part of output you sent, there is no real vibration in your system (note that imaginary frequency does not count, neither do zero frequencies). Hence, you have ZPE = 0 (exactly) and this is, in a sense, a literarily correct result because you have no vibrations...

However, this is because your potential energy surface (PES) is repulsive, and this is worrying. You are probably trying to compute frequencies for a geometry which is very far from the equilibrium one. Or you have an electronic state which has repulsive PES, so no equilibrium geometry. In both cases the computation of frequencies makes no sense. Frequencies should be computed only for stationary points on the PES, so the necessary prerequisite is to optimise geometry.

Best,
Mariusz Radon


-- 
Mariusz Radon, Ph.D.
Faculty of Chemistry
Jagiellonian University
ul. Ingardena 3
30-060 Krakow, Poland

phone: 48-12-663-22-31
e-mail: mradon at chemia.uj.edu.pl 
or mariusz.radon at uj.edu.pl
web: http://www.chemia.uj.edu.pl/~mradon


> Thank you  David
> 
> Part of output
> 
> Normal Modes of imaginary frequencies
> 
>                                  1
> Wavenumbers [cm-1]          703.06
> Intensities [km/mol]          0.00
> Intensities [relative]        0.00
>           F1X1             0.00000
>           F1Y1             0.00000
>           F1Z1             0.16223
>           F2X2             0.00000
>           F2Y2             0.00000
>           F2Z2            -0.16223
> 
> 
> Normal Modes of low/zero frequencies
> 
>                                  1           2           3           4
>      5
> Wavenumbers [cm-1]            0.00        0.00        0.00        0.00
>   0.00
> Intensities [km/mol]          0.00        0.00        0.00        0.00
>   0.00
> Intensities [relative]        0.00        0.00        0.00        0.00
>   0.00
>           F1X1             0.00000     0.16223     0.00000     0.00000
> 0.16223
>           F1Y1             0.16736     0.00000     0.00000     0.15693
> 0.00000
>           F1Z1             0.00000     0.00000     0.16223     0.00000
> 0.00000
>           F2X2             0.00000    -0.16223     0.00000     0.00000
> 0.16223
>           F2Y2            -0.15693     0.00000     0.00000     0.16736
> 0.00000
>           F2Z2             0.00000     0.00000     0.16223     0.00000
> 0.00000
> 
> 
> Zero point energy:  0.00000000 [H]        0.00 [1/CM]        0.00 [KJ/MOL]
> Frequency information read from record  5400.2
> 
> MRCI/aug-cc-pVTZ energy=   -197.671580013658
> 
> 
> 
> INPUT:
> 
> ***,F2(2+)
> memory,350,m
> gprint,orbital,civector;
> gthresh,energy=1.d-10
> symmetry,nosym
>  r  = 1.60995 ang;
> geometry={F1;
>      !z-matrix geometry input
>           F2,F1,r;
>           }
> 
> basis=aug-cc-pVTZ
> 
> {hf;accu,16;
> wf,16,1,2}
> 
> {multi;
> pspace,1;
> maxit,39;
> wf,16,1,2}
> 
> {mrci;
> pspace,1;
> wf,16,1,2}
> 
> frequencies
> 
> 
> 
> -- 
> 
> [image: ????? ?????]*Dr. David Danovich*
> The Lise Meitner Minerva Center for Computational Quantum Chemistry, Institute
> of Chemistry, The Hebrew University of Jerusalem,  Edmond J. Safra Campus -
> Givat Ram, 9190401 Jerusalem, Israel
> http://yfaat.ch.huji.ac.il/david.html, e-mail:
> david.danovich at mail.huji.ac.il <david.danovich at huji.ac.il>
> 
> FAX:(+972)-2-6584033, Phone:(+972)-2-6586934(w),  Mobile:(+972)-544-768669
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> ------------------------------
> 
> Message: 2
> Date: Thu, 29 Jun 2017 17:22:38 +0200
> From: Veacheslav <ep-silon at mail.ru>
> To: "molpro-user at molpro.net" <molpro-user at molpro.net>
> Subject: [molpro-user] Operator in AO basis
> Message-ID: <E1dQbHB-0005ud-It.ep-silon-mail-ru at smtp50.i.mail.ru>
> Content-Type: text/plain; charset="utf-8"
> 
> Dear Molpro,
> 
> Is it possible to print the orbital angular momenta matrices in the basis of atomic orbitals?
> 
> Many thanks,
> Veaceslav
> 
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