Low-temperature zigzag charge-ordering structure of α′-NaV 2O 5

Abstract

The low-temperature (LT) superstructure of NaV 2O 5 was determined by synchrotron radiation X-ray diffraction. Below the phase transition temperature at 34 K , the LT structure is monoclinic. It was determined that the LT structure is ( a− b)×2 b×4 c with the space group A112, where a, b and c represent the high-temperature orthorhombic unit cell. The valence estimation of V ions shows that the V sites are clearly separated into two groups of V 4+ and V 5+ with a zigzag charge-ordering pattern.