My Community

Hello,

I'm doing some LCHIMAG calculations with VASP and I noticed something strange. I have the following symmetric magnetic shielding tensor

275.016064, 8.323574, -0.296549
6.229964, 272.642428, -1.488598
-1.049309, -2.379348, 272.128976

The G0 contribution is

-5.198851, 0.004894, 0.000606
0.008268, -5.184956, 0.009264
0.001568, 0.009761, -5.196157

and the core contribution

-766.8301203

If I do the calculation myself by adding the G0 tensor to the symmetric
tensor and then the core contribution to the diagonal values and calculate
the isotropic chemical shift, span and skew I get the following values
-498.7610, 15.2678, -0.2515 while VASP gives me -499.2860, 15.2754, -0.2513

Am I doing something wrong? How does VASP go about considering/removing the
contributions?

Best,
Carlos

Dear Carlos,

Could you please provide all relevant input and output files for your calculation according to the forum guidelines?

Here are the files

You need to add "Core contribution to magnetic susceptibility" as well. It is provided in OUTCAR: -125.32 10^-6 cm^3/mole or
-0.5247454 ppm.

Hi Alexey,

I see, I was not aware that this needed to be added also. By the way, how did you go from the -125.32 10^-6 cm^3/mole to
-0.5247454 ppm? I don't see this last value in the OUTCAR

The conversion factor can be found in linear_response_NMR.F: The volume in your OUTCAR is 3320.6197, so -125.32/CHI_FACT = -0.525