THE SYNTHESIS AND THERMAL BEHAVIOR OF DICALCIUM CYCLO-TETRA-μ-IMIDO-TETRAPHOSPHATE

Abstract

Dicalcium cyclo-tetra-μ-imido-tetraphosphate octahydrate has been prepared by adding aqueous calcium chloride into an aqueous cyclo-tetra-μ-imido-tetraphosphoric acid solution. When the cyclo-tetra-μ-imido-tetraphosphate was heated, release of the water of crystallization was observed and a small decomposition of the imidophosphate occurred up to 210°C. The imidophosphate decomposed to produce many kinds of condensed phosphates with or without NH and NH₂ groups at a higher temperature. The sample finally changed to calcium metaphosphate.