Quantitative X-ray Absorption and Emission Spectroscopies: Electronic Structure Elucidation of Cu2S and CuS.

ABSTRACT: The electronic structures of Cu2S and CuS have been under intense scrutiny, with the aim of understanding the relationship between their electronic structures and commercially important physical properties. Here, X-ray absorption and emission spectroscopic data have been analyzed using a quantitative, molecular orbital (MO) based approach to understand the electronic structure of these two complex systems. Cu2S is shown to have a significant amount of Cu2+ sites and therefore Cu0 centers. The presence of low-valent Cu is correlated with the electrical conductivity of Cu2S, especially at high temperatures. CuS is shown to have tetrahedral Cu2+ and trigonal Cu1+ sites, with crystal planes that have alternating high and low charge on the Cu centers. These alternating charges may contribute to internal energy transitions required for photoluminescence properties. The in-depth electronic structure solutions presented here not only solve a complicated much-debated problem, but also demonstrate the strength of quantitative MO based approach to X-ray spectroscopies.

SUBMITTER: Kumar P 

PROVIDER: S-EPMC3683299 | biostudies-literature | 2013 Apr

REPOSITORIES: biostudies-literature