双(甲基环戊二烯基)二(2,6-二氯苯氧基)铪的晶体和分子结构

本文用X-射线衍射法测定了(η⁵CH₉C₅H₄)₅H₁(OC₆H₉Cl₃-2,6)₂的晶体和分子结构.晶体结构属单科晶系,空间群为P²1/c,晶胞参数为a=17.010(2)Å,b=8.577(1)Å,C=16.313(3)Å,β=101.52(3)°,晶胞内分子数Z=4.分子内有非结晶学二次旋转轴对称性,铪原子周围的两个甲基环戊二烯基和两个氧原子构成一个变形四面体.两个环戊二烯基的平面夹角为125.33°.氧-铪-氧键角为103.71°.铪-氧键长为2.004-2.022Å,较铪-氧单键键长为短,表明具有部分双键特性.

Studies on Crystal and Molecular Structure of Bis(Methylcyclopentadienyl) Di(2, 6-dichlorophenoxy)hafnium

In the present paper, the crystal and molacular structure of (η⁵-CH₃C₅H₄)₃Hf(OC₆H₃Cl₃-2,6)₃ have been determined by X-ray diffraction method. The crystallizes structure belongs to monoclinic system with space group C₂₅h-P₂1/c and cell parameters a = 17.010(2)Å, b = 8.577(1)Å, c= 16.313(3)Å,β=101.52(3)°. There are four molecules in each unit cell, Z = 4. Within each molecule there is a non-crystallographic twofold axis which lies on the (010) plane through the Hf atom parting the molecule into two similar halves.Two methylcyclopentadienyl group and two oxygen atoms around the hafnium atom form a pseudo-tetrahedron.The angle between the two methylcyclopentadienyls is 125.33°. The angle O-Hf-Ois 103.71°.The bond length Hf-Ois 2.004-2.022Å, it is shorter than Hf-O single bond. The results show clearly that Hf-O bond is characteristic of some partial double bond.