2021/07/19 by SHINOTSUKA, Hiroshi, Tanuma, Shigeo, Powell, Cedric +1
#FPA #TPP-2M #electron inelastic mean free path #elemental solid #inelastic mean free paths #predictive equation for IMFP #relativistic TPP-2M
paper · doi:10.48505/nims.3043
We have calculated inelastic mean free paths (IMFPs) for 41 elemental solids (Li, Be, graphite, diamond, glassy C, Na, Mg, Al, Si, K, Sc, Ti, V, Cr, Fe, Co, Ni, Cu, Ge, Y, Nb, Mo, Ru, Rh, Pd, Ag, In, Sn, Cs, Gd, Tb, Dy, Hf, Ta, W, Re, Os, Ir, Pt, Au, and Bi) for electron energies from 50 eV to 200 keV. The IMFPs were calculated from measured energy loss functions for each solid with a relativistic version of the full Penn algorithm. The calculated IMFPs could be fitted to a modified form of the relativistic Bethe equation for inelastic scattering of electrons in matter for energies from 50 eV to 200 keV. The average root-mean-square (RMS) deviation in these fits was 0.68 %. The IMFPs were also compared with IMFPs from a relativistic version of our predictive TPP-2M equation that was developed from a modified form of the relativistic Bethe equation. In these comparisons, the average RMS deviation was 11.9 % for energies between 50 eV and 200 keV. This RMS deviation is almost the same as that found previously in a similar comparison for the 50 eV to 30 keV range (12.3 %). Relatively large RMS deviations were found for diamond, graphite, and cesium as in our previous comparisons. If these three elements were excluded in the comparisons, the average RMS deviation was 8.9 % between 50 eV and 200 keV. The relativistic TPP-2M equation can thus be used to estimate IMFPs in solid materials for energies between 50 eV and 200 keV. We found satisfactory agreement between our calculated IMFPs and those from recent calculations and from measurements at energies of 100 keV and 200 keV.