Crystal structure and vibrational spectra of hydrazinium(2+) aquatetrafluoroindate(III), N2H6(InF4H2O)2

The crystal structure of hydrazinium(2+) aquatetrafluoroindate(III), N₂H₆(InF₄H₂O)₂, has been determined by X-ray diffraction. The compound crystallizes in the triclinic space group (C_i¹) with a = 6.759(2) Å, b = 6.228(1) Å, c = 5.7854(7) Å, = 80.28(2)°, = 88.79(1)°, = 69.96(2)°, V = 225.3(1) ų, and Z = 1. The structure comprises hydrazinium(2+) cations and InF₂F_4/2O^– anions in which In appears to be seven-coordinated in the form of a pentagonal bipyramid by four bridging fluorine atoms, two terminal fluorine atoms, and one oxygen atom. Pentagonal bipyramids are interconnected and form chains along a axis. Bands in vibrational spectra were assigned to the vibrations in N₂H₆²⁺ cations and anionic InF₂F_4/2O^– entities. The rather intensive band appearing at 1042 cm^–1 in Raman spectrum, which is absent from infrared, is characteristic of the N₂H₆²⁺ cation, in line with the predictions of the unit-cell group analysis for the studied system.