A New Member of Giant Polyoxomolybdate Containing Bridging Hydroxylamine Moieties: Synthesis and Crystal Structure of (NH4)4Na2[MoVI36O108(NH2OH)2(OH)6(H2O)12]·35H2O

A new member of giant polyoxomolybdate containing bridging hydroxylamine groups has been unexpectedly obtained during the preparation of the material of {Mo₅₇V₆}, (NH₄)₄Na₂[Mo₃₆^VIO₁₀₈(NH₂OH)₂(OH))₆(H₂O)₁₂] · 35H₂O. The title compound crystallizes in the monoclinic space group P2(1)/n, a= 16.7886(2), b = 18.4309(3), c = 24.49950(10) Å, β = 99.58°, V = 7475.18(15) ų, Z = 2, and D_calc = 2.817. Each giant cluster anion [Mo₃₆^VIO₁₀₈(NH₂OH)₂(OH)₆ (H₂O)₁₂]^6- ({Mo₃₆(NO)₂}) consists of two large [Mo₁₅^VIO₅₀(MoO₂⁴⁺(µ-NH₂(OH) (µ-OH)(t-OH)₂(t-OH₂)₆]^5- ({Mo₁₇} units linked together by two {MoO₂}²⁺ centers; these anions {Mo₃₆(NO)₂} are further connected via distorted monocapped pentagonal-pyramidal sodium into a three-dimensional structure with channels that filled with lattic water molecules and NH₄⁺ ions. KEY WORDS: Giant polyoxomolybdate; synthesis and crystal structures; bridging hydroxylamine groups. [ABSTRACT FROM AUTHOR]