Structural and electronic properties of the KTiOAsO4(0Â 0Â 1) surface

Crystallographic and electronic parameters of KTiOAsO4 (KTA) (0 0 1) surface have been studied with reflection high energy electron diffraction (RHEED) and X-ray photoelectron spectroscopy (XPS). From analysis of RHEED patterns the superstructure formation has been detected with the relations a = a0, b = 2b0 and c = 2c0 were a0, b0 and c0 are the cell parameters of KTA bulk. Results of the core-level spectroscopy are discussed in comparison with those obtained earlier for other crystals belonging to the KTP family. The relationship between crystal structure variations and chemical shifts of binding energy of constituent element core-levels induced by element substitution or doping has been considered for a set of KTP family crystals including KTiOPO4, KTiOAsO4, TlTiOPO4 and K0.77Ti0.77Sb0.23OPO4.