1,2,3,4-四苯基丁二烯二环戊二烯铌的合成和顺磁共振研究

Preparation and EPR Studies of 1,2,3,4-Tetraphen ylbutadienebis(Cyclopentadienyl)Niobuim(Ⅳ)

合成1,2,3,4-四苯基丁二烯二环戊二烯妮(Ⅳ)金属环化合物.测定它的甲苯溶液和玻璃态固体多晶EPR波谱.由计算机模拟分析得到各向异性EPR参数:g_(x)=1.9915,g_(y)=2.0017,g_(z)=2.0005;T_(x)=-69.5G,T_(y)=-103.2G,T_(2)=-18.0G和最高占据分子轨道中d_(z2)及d_(x^(2)-y^(2))混合系数比α^(2)/b^(2)=22.0.

The synthesis of metallacyclic derivative of niobocene dichloride,1,2,3,4-tetraphenylbutadienebis(cyclopentadienyl)niobium(Ⅳ)are described.Solution and frozen-glass EPR spectra are measured.From computer simulation of the frozen-glass spectrum of Cp3NbC4ph4,the values of the principal components of the g and T tensors are gx=1.9915,g_(y)=2.0017,g_(2)=2.0005;Tx=-69.5G,Ty=-103.2G,T_(2)=-18.0G.The observed anisotropy for the hyperfine interaction arises from the admixture of 4d22 and 4d_(x^(2)-y^(2))character in the HOMO,The ratio of mixing coefficients,a2/b2=22.0.