Ionic species and linkage in ZnBr 2–KBr melts

Abstract

Structural analyses of (1− x)ZnBr 2– xKBr melts were made by time-of-flight pulsed neutron diffraction. The interatomic distance r ij of the nearest neighbor Zn–Br pair was estimated at about 2.4 Å which was shorter than the sum of ionic radii 2.56 Å, indicating the existence of covalent bonding. Furthermore, the co-ordination number n ij of the corresponding pair was calculated to be around 4 and the ratio of r Br–Br to r Zn–Br was about 1.6 which was nearly equal to tetrahedral geometry 8/3 , implying the tetrahedral configuration. Addition of KBr to ZnBr 2 made the linkage of ZnBr 4 2− tetrahedral clustering units break into pieces.