Synthesis and crystal structures of lithium polyphosphates, LiPO3, Li4H(PO3)5, and LiMn(PO3)3

Polyphosphates of the compositions LiPO3, Li4H(PO3)5, and LiMn(PO3)3 were prepared by the reactions of Li2CO3 and MnO2 with melts of polyphosphoric acids at 240–350°C, and their crystal structures were established. The unit-cell parameters are a = 13.074 Å, b = 5.4068 Å, c = 16.452 Å, β = 99.00°, sp. gr. P2/n; a = 6.6434 Å, b = 7.253 Å, c = 11.399 Å, α = 72.60°, β = 83.36°, γ = 85.32°, sp. gr.; P 1 ; a = 8.364 Å, b = 8.561 Å, c = 8.6600 Å, sp. gr. P212121, respectively. The influence of cations on the structures of the compounds is discussed.