VPT2 calculation at aug-cc-pVTZ-F12/CCSD(T)-F12a level

[Snigda Brijesh]

Dear Molpro Community,

I'm trying to perform a VPT2 calculation in Molpro at the aug-cc-pVTZ-F12/CCSD(T)-F12a level of theory for HF. I used the VPT2 example on the Molpro website for water (link below) as a template:

https://www.molpro.net/manual/doku.php?id=vibrational_perturbation_theory_vpt2

Here is my input file:

***, HF
memory,800,m
basis=aug-cc-pvtz-f12
orient,mass
geometry={
   2
  HF
 F                  0.00000200    0.00000000    0.4589072812
 H                  0.00000000    0.00000010   -0.4589072812
}

mass,iso

hf
ccsd(t)-f12a
optg                                     !(1) optimizes the geometry
frequencies,symm=auto                    !(2) compute harmonic frequencies

label1
{hf
start,atden}
ccsd(t)-f12a

{xsurf,start1D=label1,sym=auto           !(3) generate a QFF
 vtaylor,type=qff
 disk,where=home,dump='cmp2.pot'}
poly,type=qff,vam=0                      !(4) transform the PES to polynomials
vpt2                                     !(5) do a VPT2 calculation

However, when I run this input, I frequently encounter the following error:

READM: TRYING TO READ BEYOND RECORD BOUNDARY

I have tried a few minor changes but can't seem to resolve this issue. I suspect I might be missing something important related to either the method, the way the QFF is generated, or how the disk dump file is handled.
Could anyone please advise what might be causing this error or how I could modify my input to successfully perform a VPT2 calculation at this level?

Thanks and regards,

Snigda

[rauhut]

Dear Snigda,

the VPT2 program has not been designed to handle diatomic molecules. For that particular purpose you should use the TABLE command in combination with the DIATOMIC option. See the manual.

Best,

   Guntram

[Alex Brown]

Dear Guntram,

Thanks for the reminder about the “special treatment’ for diatomics - I was working with Snigda on this project. 

However, I will note that we have seen the same error "READM: TRYING TO READ BEYOND RECORD BOUNDARY” for tetra-atomics. Input is analogous to the example below with the only difference being the 

geometry block. Could this be a symmetry issue?

Cheers,

Alex

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Professor and Department Chair

W4-70D Gunning/Lemieux Chemistry Centre

Department of Chemistry

University of Alberta

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T6G 2G2

Phone: 780-492-1854

http://alexbrown.chem.ualberta.ca

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