[CHM 331] Re: TMS nmr shifts

[Andrew J. Pounds]

  Try this...

   1.   Run the TMS Optimization.
   2.   When it completes, allow Gaussian to open the Checkpoint file.
   3. CLOSE the window that has the original molecule (with the .gjf
      extension)
   4. Click on the window that has the optimized molecule in it (it
      should be called tm3b3lyp.chk)
   5. Now go to the Calculate->Gaussian selection box.  Make sure  that
      the method and basis set are the same.  Select the NMR calculation
      type.  Also make sure you change the name of the checkpoint file
      to tmsnmr.chk and submit the calculation.  When prompted, save it
      as tmsnmr.gjf
   6. When this job completes open the output log file (TMSNMR.LOG).  Go
      down to the NMR section and look for the isotropic magnetic
      shielding values.  They will be similar for the same atoms -- but
      should not be identical as in the output you sent me.   Average
      the values for hydrogen and then average the values for carbon.
   7. Repeat 1-6 for benzene and subtract the H and C values for TMS
      from those found in benzene.  These values should be "close" to
      the literature values.
   8. As always -- let me know if you are still having problems.


On 11/16/2011 03:20 PM, Vanessa.Marie.Breslin wrote:
> Dr. Pounds,
>
> I've run the TMS nmr shift calculation more than 4 times now and I'm 
> still getting the exact same numbers for the C's and H's. I ran the 
> nmr shift for benzene and got slightly different numbers, so I don't 
> know what's wrong with my TMS calculations. I've attached the files 
> for you to look at.
>
> Thanks,
> Vanessa

-- 
Andrew J. Pounds, Ph.D.  (pounds at theochem.mercer.edu)
Associate Professor of Chemistry and Computer Science
Mercer University,  Macon, GA 31207   (478) 301-5627

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://theochem.mercer.edu/pipermail/chm331/attachments/20111116/a7c34ded/attachment.html