Nonapiperidinium monohydrogen deca-vanadate tetra-nitrate

The title compound, (C(5)H(12)N)(9)[HV(10)O(28)](NO(3))(4), contains a monoprotonated deca-vanadate polyanion which lies on an inversion center. All the piperidinium cations adopt chair conformations. In the crystal structure, inter-molecular N-H⋯O hydrogen bonds form chains along [001]. As well as half of a polyanion, the asymmetric unit contains one full and two half-occupancy nitrate ions and four full occupancy and one half-occupancy piperidinium cations; the half-occupancy piperidinium cation is disordered over two general sites with occupancies of 0.32 and 0.18, and is, in turn, disordered over an inversion center.