[Wien] A question about the value of energy loss in TELNES.2

[Ruijuan Xiao]

Dear all,

When I use the TELNES.2 to calculate energy loss near edge spectrum, I found that the value of the energy loss(x axis) in the simulated spectrum begins from "0". In the past, I always shift this x axis and make the onset of the theoretical spectra to well align with the experimental one, and make some comparison between them. I do not think there is any problem.

But recently, someone asked me about the meaning of the x axis. He emphasized that the value of energy loss is the difference between the energies of final and initial states, so there should be an absolute value calculated from the program, and any shift of the theoretical energy loss to compare with the experiments does not make sense. I do not know how to explain it to him. So I wonder why the program gives a theoretical spectrum starting from zero instead of calculating the absolute value of energy loss. Is it because some initial states are core states, their energies can not be calculated as accurately as valence states?
                                                                    
I also searched in this mailing list, and found some statements related to this question. It says "the '0' of the elnes spectrum corresponds to the threshold energy that you specify in case.innes.  So the 'real' energy loss is given by that on the x-axis, plus the threshold energy of case.innes.". But it seems that the threshold energy specified in case.innes is given by the user, so it can not reflect the real energy loss of the spectrum.

I am looking forward to your reply. Thank you very much in advance. 


Best regards,

Sincerely,
Ruijuan