I’m asked to calculate emission spectra under crystal field. But I found no description about what these spectra are, and I’m under the impression that it might be inelastic neutron spectra ( judging from the examples and concept page).
I’m wondering could these functions be used for emission spectra?
I’m not exactly sure what you mean by “emission spectra” - you can measure an emission spectrum with neutrons or any other other radiation (e.g. light [infrared] or electrons).
Inelastic neutron spectroscopy is an emission process where the emitted radiation is measured rather than the absorption of the incident radiation, but the term “emission spectroscopy” is more usually applied to optical/photon spectroscopy.
The main difference between the techniques is the energy scales which each technique measures. With neutrons (INS) the energy scales which can be measured is usually lower than in optical spectroscopy - usually from 1-100meV (10-1000 cm-1 or 0.1-10 THz). Typical optical spectra extend to higher energies (100-10000cm-1).
Mantid was designed to model neutron data so it does not calculate these higher energy modes (above 1000cm-1). Thus if you want to model optical emission spectra you should use a different program such as pycrystalfield or spectre ( Andrew Boothroyd: Software | University of Oxford Department of Physics )