STUDIES ON ORGANOMETALLIC COMPOUNDS OF TITANIUM,ZIRCONIUM AND HAFNIUM——THE CRYSTAL AND MOLECULAR STR

来源 :Science in China,Ser.B | 被引量 : 0次 | 上传用户:tobydu
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
This paper reports the crystal and molecular structures of tetrakis (cyclopentadienyl) bis(o-tolyl)-μ-oxo-dizirconium [dimer (Ⅰ)] and tetrakis (methylcyclopentadienyl) bis (p-tolyl)-μ-oxo-dizirconium [dimer (II)]. Both of them belong to monoclinic system and possess the same spacegroup C_2~5h- 2_1/a. The cell dimer (Ⅰ) containing four molecules is defined by a=19.122A,b=16.319A, c = 9.296A, β= 92°1′; the cell dimer (Ⅱ) containing two molecules is defined bya = 20.076A, b = 8.205A, c = 10.016A, β= 104°41′. The important difference of molecular configurations between the two dimers lies in thatthe dimer (Ⅰ) has no symmetry center and its Zn-O-Zr oxo-bridge presents a slightly bentconfiguration while the dimer (Ⅱ) takes the oxgen atom as a symmetry center and its oxo-bridge present linear linkage. In accordance with the above-mentioned molecular configuration, steric effect and elec-tronic structure have been further discussed. This paper reports the crystal and molecular structures of tetrakis (cyclopentadienyl) bis (o-tolyl) -μ-oxo-dizirconium [dimer (I)] and tetrakis (methylcyclopentadienyl) bis (p- tolyl) -μ- oxo-dizirconium [dimer (II)]. Both of them belong to monoclinic system and possess the same space group C_2-5h-2_1 / a. The cell dimer (I) contains four molecules which are defined by a = 19.122A, b = 16.319A, c = 9.296 A, β = 92 ° 1 ’; the important difference of the molecular configurations between the two dimers lies in that the dimer (I) has no symmetry center and its Zn-O-Zr oxo-bridge presents a slightly bent configuration while the dimer (II) takes the oxgen atom as a symmetry center and its oxo-bridge present linear linkage. In accordance with the above-mentioned molecular configuration, steric effect and elec-tronic structure have been further discussed.
其他文献
目的:研究手术配合护理在白内障超声乳化联合人工晶体植入术中的应用效果.方法:选取2018年5月至2020年5月于我院进行白内障超声乳化联合人工晶体植入术的患者96例,并将其随机
目的:研究门诊西药房中应用PDCA循环对药品差错的影响.方法:本次研究开展年限区间范围为2018年8月至2019年8月,2018年8月-2019年8月期间我院门诊西药房未实施PDCA循环管理,20
目的:关于阶梯式肺康复护理手段应用在重症急性呼吸窘迫综合征患者当中的效果分析.方法:本项目自2019年3月起,到2020年7月结束,研究期间共入组重症急性呼吸窘迫综合征患者90
目的:观察将预见性护理程序应用在冠心病护理中取得的临床效果.方法:随机挑选我院2018年2月至2019年2月接诊的冠心病患者86例.按照入院顺序将其分为两组,两组患者例数都有43
Based on the discrete form of the main governing equation derived, a single wave as the main motion of the instability analysis was found. This solution gives
目的:对健康教育护理干预应用在风湿性心脏病患者护理中的干预效果进行调查.方法:以我院64例风湿性心脏病患者为调查样本,采用随机分组的方式分为两组,人数相等,观察组在对照
目的:分析护理干预在神经内科支架术后护理中的应用效果.方法:选取278例神经内科支架术患者作为本次研究对象,按随机数字表法将其分为实验组与对照组,各139例,对照组给予常规
请下载后查看,本文暂不支持在线获取查看简介。 Please download to view, this article does not support online access to view profile.
目的:探讨ICU优质护理的开展对于大型口腔颌面部肿瘤根治术患者术后恢复的影响.方法:将74例接受大型口腔颌面部肿瘤根治术治疗的患者分为观察组(ICU优质护理)和对照组(常规护
目的:探讨重症加强护理病房(ICU)患者谵妄的原因及护理措施.方法:回顾性分析,抽取2019年5月至2020年5月我院ICU收治的100例患者资料,发生谵妄患者纳入发生组,未发生谵妄患者