Accurate valence band width of diamond
نویسندگان
چکیده
An accurate width is determined for the valence band of diamond by imaging photoelectron momentum distributions for a variety of initialand final-state energies. The experimental result of 23.060.2 eV agrees well with first-principles quasiparticle calculations ~23.0 and 22.88 eV! and significantly exceeds the localdensity-functional width, 21.560.2 eV. This difference quantifies effects of creating an excited hole state ~with associated many-body effects! in a band measurement vs studying ground-state properties treated by local-density-functional calculations. @S0163-1829~97!05136-9#
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