Charge density distribution of transparent p-type semiconductor (LaO)CuS

The charge density distributions of layered oxysulfide (LaO)CuS, known as a p-type transparent semiconductor, have been investigated by analyzing the synchrotron radiation powder diffraction profile with the maximum entropy method/Rietveld method. The bonding character of the Cu-S bond is revealed to be covalent. Meanwhile, the O-La bonding has both ionic and covalent characters. The number of electrons estimated by integrating the charge density around each atom gave direct evidence that each CuS and LaO layer is electrically almost neutral. (c) 2007 American Institute of Physics.