Preparation of Barium-Containing Silicon Clathrate Compound

Abstract
A new silicon clathrate compound containing Ba was prepared by the thermal degradation of a solid solution (Na2Ba)Si4 at 500°C in vacuum. The compound has the Na8Si46 clathrate type structure, which consists of silicon tetrahedral networks having two types of cages, pentagonal dodecahedra and 14-face polyhedra. The Ba atoms are placed only in the larger cages.