Octasodium bis-(Nitrilo-tris-Methylenephosphanatooxovanadate(IV))-Dioxo-bis-Oxovanadium(IV) Icosohydrate Na8[(VO)2(μ−O)2{(VO)μ3−N(CH2PO3)3}2]·20H2O

Abstract

Crystal hydrate of sodium salt of an oxovanadium(IV) complex with nitrilo-tris-methylenephosphonic (NTP) acid Na₈[(VO)₂(μ−O)₂{(VO)μ³−N(CH₂PO₃)₃}₂]·20H₂O is synthesized, isolated, and studied: space group P1̅, Z = 2, a = 12.5829(2) Å, b = 13.9297(2) Å, c = 15.1051(3) Å, α = 72.233(2)°, β = 76.907(2)°, γ = 70.388(2)°. The NTP ions are completely deprotonated and hexadentate. In coordinating the VO²⁺ ion each NTP ion closes three N–V–O–P–C cycles with a common N–V bond. By means of bridging vanadyl ions and oxo ligands the four-membered V–O–V–O cycle and the [–V–O–P–O–]₄ macrocycle are closed. Coordination V polyhedra are distorted tetragonal pyramids. With regard to the occurrence of weak V–N bonds the polyhedra of two V atoms can be completed to strongly distorted octahedra.