［N(CH3)4］4［Mo10O18(OH)4(O2)10(O2)2］·6H2O的合成、晶体结构及表征

以质量分数30%过氧化氢为氧化剂,钼酸铵和四甲基氯化铵为原料,室温下采用常规的水溶液法成功制备了一种含有过氧与超氧基团的十核钼酸四甲基铵盐［N(CH₃)₄］₄［Mo₁₀O₁₈(OH)₄(O₂)₁₀(O₂)₂］·6H₂O,并对其进行了元素分析、红外光谱、紫外光谱表征及X线单晶结构分析.该化合物属于单斜晶系,P2₁/c空间群,a=1.443(16)nm, b=1.168(12)nm, c=1.693(17)nm,β=99.32(3)°, V=2.814(5)nm³, Z=2, D_c=2.441 g/cm³, R₁=0.035 6, wR₂=0.105 0(I>2, GOF=1.087.其阴离子呈中心对称结构,包含2个键长为0.114 5 nm的超氧基团和10个键长为0.143 5~0.148 1 nm的经典过氧基团.此化合物溶于水不稳定,但在室温下能稳定存在于固态,并能迅速将I^- 氧化成单质I₂,表明了该化合物由于结构中过氧和超氧基团的存在而具有强氧化性.

Synthesis,crystal structure and characterization of ［N(CH3)4］4［Mo10O18(OH)4(O2)10(O2)2］·6H2O

A new tetramethyl ammonium decamolybdate ［N(CH₃)₄］₄［Mo₁₀O₁₈(OH)₄(O₂)₁₀(O₂)₂］·6H₂O with peroxo and superoxo groups was synthesized by reacting of 30% hydrogen peroxide as the oxidant, ammonium molybdate and tetramethyl ammonium chloride in aqueous solution at room temperature. The compound was characterized by elemental analysis, IR, UV spectroscopy and Its structure was determined by single crystal Xray diffraction. The compound belongs to monoclinic system with space group P2₁/c, a=1.443(16)nm, b= 1.168(12)nm, c= 1.693(17)nm, β= 99.32(3)°, V=2.814(5)nm³, Z=2, D_c=2.441 g/cm³, R₁ = 0.035 6, wR₂ = 0.105 0(I>2, GOF=1.087. The compound anions exhibit a centrosymmetric structure containing two superoxo groups with a bond length of 0.114 5 nm and ten classical peroxo groups with a bond length range of 0.143 5~0.148 1 nm. The compound is unstable in water, but stable in solid state at room temperature, and can rapidly oxidize I^- into I₂ with the yield of iodine reaching 91.2%, indicating the compound has strong oxidizing properties due to peroxo and superoxo groups in the structure.