Abstract
α-Mg
3[BPO
7] (low temperature form) which is isostructural with Zn
3[BPO
7] has been synthesized by the solid-state reactions of MgHPO
4.H
2O with MgCO
3 and H
3BO
3 at 1200°C, Mg
3B
2O
6 with MgCO
3 and (NH
4)
2HPO
4 at 1100°C, and MgO with B
2O
3 and P
2O
5 at 1100 with the molar ratios of 1:2:1, 1:3:2 and 6:1:1, respectively. The structure of α-Mg
3[BPO
7] was found to be orthorhombic (as already reported), with refined unit cell parameters of
a=8·495(3),
b=4·886(1) and
c=12·565(4) Å; the space group is Immm with Z=4. The indexed X-ray powder diffraction data and the IR spectrum of α-Mg
3[BPO
7] are also given. The latter reveals trigonal planar coordination of boron.