Wrong shielding value from NMR calculation

[vweber]

Hi Lekpa

Running g03 gives me the following shift for your systems

mono_nmr.out:  2  Si   Isotropic =   385.4381   Anisotropy =
33.7255
tms_nmr.out:  1  Si   Isotropic =   349.7620   Anisotropy =     0.0699

and the cp2k (cvs) gives
mono-nmr-SHIFT-1.data:  ISOTROPY =     384.7861  ANISOTROPY =
36.7078
tms-nmr-SHIFT-1.data:  ISOTROPY =     351.1586  ANISOTROPY =
1.5007

I would suggest you to use the GAUGE ATOM in the CURRENT section and
you would get

mono-nmr-SHIFT-1.data:  ISOTROPY =     385.9543  ANISOTROPY =
33.9237
tms-nmr-SHIFT-1.data:  ISOTROPY =     349.5128  ANISOTROPY =
0.1374

which are slightly closer to the g03 runs.

What is the value you get with the other software?

V


On Mar 9, 10:24 am, Lekpa Duukori <duu... at gmail.com> wrote:
> Dear All,
>
> I am having some problems with nmr calculations using cp2k.
> I am using a 2009-02-11 compilation.
>
> I am trying to calculate chemical shifts and I started with the silicate
> monomer (Si(OH)4).
> The following shielding values was obtained
>
> Monomer: ISOTROPY =     385.1320  ANISOTROPY =      35.3885
> TMS:         ISOTROPY =     350.0942  ANISOTROPY =       0.6521
>
> The value for TMS is close to what I obtain using other software but for the
> monomeric specie,
> its way off.  Does anyone know what might be the cause of this ?
>
> My input files are attached.
>
> Thanks.
>
> Lekpa.
>
>  files.gz
> 2KViewDownload