The crystal structure of dicalcium phosphate, CaHPO 4

Abstract

Anhydrous dicalcium phosphate has been found to be triclinic with space group P1, the cell dimensions being a-6.904-0.01, b-6.65±0.01, c-7.00:k0.01 A; a-96 °21', fl-103 °54', 7-88°44'. The atomic coordinates have been found by analysis of the three-dimensional Patterson function, and the struct:~re has been refined to a residual error factor R-0.20. The structure contains independent PO4 groups, one kind of calcium atom having a coordination of seven and the other of eight oxygens. Visual estimates of intensities were employed and the errors in these are considered to be too large to enable the positions of the hydrogen atoms to be found.