The electronic structures of vacancies at the (VO)2P2O7(100) surface were studied by using a cluster model. One particular type of surface O monovacancy was considered. This was the neutral Fs0 center: that is, a vacancy with 2 trapped electrons. The energetics

of defect formation, and the effect of electron trapping upon the atomic arrangement, were considered. It was shown that the vacancies significantly modified the physical and chemical properties of this surface, and influenced its catalytic behavior.

Changes of Local Electronic Structure of Perfect (VO)2P2O7(100) Surface in Response to Oxygen Vacancy Formation. A.Haras, H.A.Duarte, D.R.Salahub, M.Witko: Surface Science, 2002, 513[2], 367-80