Monoammonium Trimetaphosphimate (NH4)H2(PO2NH)3

Trimetaphosphimates show a rich structural variability in both cation coordination and anion arrangement. They are precursors for crystalline, as well as amorphous oxonitridophosphates. The ammonium trimetaphosphimate (NH4)H-2(PO2NH)(3) is formed during the decomposition of the corresponding acid in solution. The monoclinic crystal structure of the monoammonium salt was elucidated by single crystal X-ray diffraction using synchrotron radiation. The trimetaphosphimate monoanions exhibit a twist conformation and form crankshaft-like stacks along [100], which have so far only been observed in (NH4)(3)(PO2NH)(3)center dot H2O and Ag-3(PO2NH)(3). (NH4)H-2(PO2NH)(3) decomposes at 170 degrees C, forming a poorly crystalline phase. Therefore, it is a model system and possible precursor for the synthesis of oxonitridophosphates.