Model dielectric function critical points

Visible-to-Vacuum-Ultraviolet Model Dielectric Function Band-to-Band Transitions and their Critical-Point Structures... 

Fig. tr.1-157 ZnS, cubic. Dielectric-function spectrum e E), measured by spectroscopic ellipsometry at 300 K after chemomechanical polishing of the sample (circles). The solid lines show values calculated from a model dielectric function for interband critical points. The dashed lines represent the best-fit standard critical-point lineshapes [1.132]... 

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