EasySpin forum

Dear Stefan,

I have a question regarding the quadrupolar term in easyspin. I simulated the Zeeman diagram from a paper of a Tb(III) ion, including the quadrupolar interaction. For some reason in order to obtain the simulation as in the paper I have to multiply the quadrupolar value given in the paper exactly by 4. (the quadrupolar term in the paper is: P{Iz^2 1/3I(I+1)})

I thought the quadrupolar term in easyspin and the paper were similar. Do you have any idea what is the reason for this?

Thanks in advance!

Best wishes,

Eufemio

Please post a short script and the link to the paper, so we can have a look.

Sure, this is the link to the paper (http://onlinelibrary.wiley.com/doi/10.1 ... 8/abstract). The Zeeman diagram is the one in Figure 3. The Script is:

Sys.g = [3/2];
Sys.S = [6];
Sys.Nucs = '159Tb';
Sys.A = [A]*clight/1e4;
Sys.Q = 4*[Q]*clight/1e4; %To reproduce the Zeeman diagram I have to multiply the Quadrupolar term by 4!
Sys.B2 = alpha*[0 0 B20 0 0]*clight/1e4;
Sys.B4 = beta*[B44 0 0 0 B40 0 0 0 0]*clight/1e4;
Sys.B6 = gamma*[0 0 B64 0 0 0 B60 0 0 0 0 0 0]*clight/1e4;

Alpha, beta and gamma are constants related to the Tb ion.

Cheers

Please post a self-containing script that gives all the constants and also the function call so that we can run it. Thanks!

Attached is the script file.
Best,
Eufemio

This is correct. If you give a single number for Sys.Q, EasySpin understands it as e^2Qq/h.

The term given in the paper, P*(Iz^2-I(I+1)/3), corresponds to P/3*(-Ix^2-Iy^2+2*Iz^2). If you look at the EasySpin reference page on the nuclear quadrupole interaction, the prefactor P/3 is equal to e^2Qq/h/(4I*(2I-1)). The denominator in the last expression is 12, so this means P/3 = e^2Qq/h/12. From this e^2Qq/h = 4*P.

Perfect, thanks for the explanation Stefan!
Cheers,
Eufemio