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1.
Paul J. Dyson Petra Escarpa Gaede Brian F. G. Johnson John E. McGrady Simon Parsons 《Journal of Cluster Science》1997,8(4):533-545
On reaction with Ru3(CO)12, isopropenylbenzene and 4-phenyl-l-butene undergo hydrogenation, to yield the clusters, Ru6C(CO)14(6-C6H5CHMe2) 1 and Ru6C(CO)14(6-C6H5C4H9) 2, respectively. With allylbenzene, both hydrogenation and isomerization occurs affording Ru6C(CO)14(6-C6H5C3H7) 3 and Ru6C(CO)14(6-C6H5C3H5) 4. The structures of 1 and 2 have been established by single crystal X-ray diffraction. One of the Ru–Ru bond lengths in 2 is unusually long and extended Hückel molecular orbital calculations have been used in an attempt to rationalize this feature. 相似文献
2.
采用自洽场分子轨道UHF/6-31G**从头算法,研究了1,2-C4H6→2-C4H6异构化反应机理,优化了基态势能面上反应物、过渡态、中间体和产物的几何构型,并对各驻点能量进行了零点能校准.结果表明该反应经历一个1-甲基环丙烯生成产物比经两步氢迁移反应历程更易发生. 相似文献
3.
用常规合成方法制备了基于Anderson结构阴离子的二维层状化合物[(C6H5NO2)2Pr(H2O)4](CrMo6O24H6)·2.5H2O,通过红外光谱和X射线单晶衍射对其进行了表征.结果表明,该化合物属于单斜晶系,C2/c空间群.a=2.3442(9)nm,b=1.3291(5)nm,c=2.458(1)nm,β=103.08(1)°,V=7.460(5)nm3,R1=0.0727,wR2=0.1903.结构分析表明,[CrMo6O24H6]3-阴离子通过端氧担载一个配位的Pr3+离子形成中性的(C6H5NO2)Pr(H2O)4(CrMo6O24H6)基团,相邻的中性基团在Ot—Pr—Ot桥联下形成一维链,链与链又通过异烟酸的桥联形成二维层状结构. 相似文献
4.
以三聚氰胺和硼酸为原料在水溶液中反应合成出了一种新的BCN化合物先驱体C3N6H6(H3BO3)2。XRD表征结果表明三聚氰胺和硼酸的最佳配比为1∶3(物质的量比)。用单晶X-射线衍射分析法测定了该化合物的晶体结构。该化合物属单斜晶系,空间群为P21/C,晶胞参数为a=0.3597(7)nm,b=2.0105(4)nm,c=1.4112(3)nm,α=90,°β=92.07(3),°γ=90,°V=1.0199(3)nm3,Z=4,D c=1.627g.cm-3,μ(MoKα)=0.144mm-1,F(000)=520。晶体结构经全矩阵最小二乘法修正,最终可靠因子R1=0.0519,wR2=0.1361。该化合物是由C3N6H6分子和H3BO3分子通过氢键加合组装形成的三维超分子结构化合物。 相似文献
5.
在结构化学的教学中,常常要讨论二硼烷(B2H6)等“缺电子分子”的几何结构和化学键的性质.二硼烷的几何结构已早有定论,因为无论是它的化学性质,还是包括电子衍射、核磁共振、X-射线在内的广泛物理化学研究,都表明两个硼原子与四个端氢原子共平面,另外两个氢原子在平面的上下(如图所示).而且,该分子结构中存在三中心双电子化学键也为大家普遍接受.然而,关于B2H6分子中三中心化学键的解释在教科书中却各持己见,甚至同一本书中有两种不同的观点[1]. 相似文献
6.
用量子化学PM3半经验方法研究了P4H6各种构象的稳定性,说明P-H键与相邻磷原子的P-P键处于邻位时的构象较稳定 相似文献
7.
The statistical properties of vibrational energy levels in C6H6 are analyzed. The results show that they belong to a completely different type, of which the spectral rigidity is larger but the fractal dimensional function is smaller than both the Wigner law and Poisson law, and this new statistical property is called the low Poisson law. In fact, this special statistical property reflects the speciality in the structure of C6H6 in a way. 相似文献
8.
如何计算与测量多组元体系的活度系数,是一个重要问题。我们的工作是选取了磷酸三丁酯(TBP)与硫国酰基三氟丙酮(TTA)溶于苯的体系,进行了实验测量与理论计算,理论与实验取得了基本一致的结果。 相似文献
9.
本文对C_6H_6Cl_6不同的三氢正电集团、独立双氢正电集团与溶媒的耦合适应性进行了研究,讨论了这些正电性集团对溶媒化程度的影响,并预测了一些物质的相对溶解度,阐述了C_6H_6Cl_6异构体间熔点差异的原因. 相似文献
10.
采用自洽场分子轨道UHF/6-31G**从头算法,研究了1,2-C4H6→2-C4H6异构化反应机理,优化了基态势能面上反应物,过渡态,中间体和产物的几何构型,并对各驻点能量进行了零点能校准。结果表明该反应经历了一个1-甲基环丙烯生产产物比较两步氢迁移反应历程更易发生。 相似文献
11.
<正> (C6H5COCHCOC6H5)SmI2(THF)3,Mr= 843. 75,triclinic space group P1,a=13. 274(3),b=9. 886(3),c= 12. 526(4)A,a= 110. 89(3),B=93. 98(2),y=85. 16(2) ,V=1528. 9(8)A3,Z=2,Dc=1. 83g/cm3, (MoKa) = 0. 71069A,u= 40. 3cm-1,F(000) - 810. The structure was solved by Patterson and Fourier techniques and refined by least-squares method to a final conventional R value of 0.082(Rw= 0. 083). The central Sm(III) ion is coordinated by two iodine ions, two oxygen atoms from C6H5COCHCOC6H5 and three oxygen atoms from three THF molecules to form a distorted pentagonal bipyramid. The Sm-I distances are 3. 103 and 3. 092 A ,The Sm-O (O atom from C6H5COCHCOC6H5) distances are 2. 273 and 2. 307 A and the average Sm -O(THF) distance is 2. 500A. 相似文献
12.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1990,46(3):419-424
The infrared, Raman and inelastic neutron scattering (INS) spectra of TSA·6H2O and TPA·6H2O are in agreement with those expected for the presence of H5O+2 ions. Force fields for different assignment schemes are compared with the observed vibrational frequencies and the INS spectral profile. All but two schemes are eliminated. Whilst low-resolution INS spectroscopy cannot distinguish between these two schemes, the orientations of the vibrational ellipsoids for one scheme are in better agreement with those reported from low-temperature crystallographic studies of the H5O+2 ion. 相似文献
13.
Based on the wavefunctions obtained in the calculation of C-H stretching overtones of C6H6 and C6D6 molecules,the visible and infrared transition intensities of the molecules for C-H stretching overtones up to as high as v=0 are described by the Iachello-Oss algebraic model on the symmetric bases. The formula for Raman transition is also given. The operators for the transition are constructed according to the symmetry of the molecule. The construction of the symmetric bases is greatly simplified by using the symmetrized boson representation technique. Combining with the overtones calculation,the present work shows the vibration mode of C-H stretching is the local mode,which is consistent with other works. The agreement between the calculated results and observations is very good. The agreement indicates that the coupling between C-H stretching mode and other modes is weak or the coupling effects can be absorbed in the adjustment of parameters. The high precision calculation of the properties of molecules can be achieved by the algebraic model with fewer parameters compared with the traditional method. It also indicates that the combination of algebraic model and the symmetrized boson representation technique is a very powerful tool for describing the vibration of molecules. 相似文献
14.
15.
1 INTRODUCTION Metal organophosphonates have attracted considerable attention for over three decades due to their potential or practical applications, include- ing ion exchanges[1, 2], molecular sensors[3] and optics[4, 5]. Recently, a number of porous m… 相似文献
16.
用常规合成方法制备了基于Anderson结构阴离子的二维层状化合物[(C6n5NO2)Pr(H2O)4](CrMo6O24H6)·(C6H5NO2)·2.5H2O,通过红外光谱和X射线单晶衍射对其进行了表征.结果表明,该化合物属于单斜晶系,C2/c空间群.a=2.3442(9)nm,b=1.3291(5)nm,c=2.458(1)nm,β=103.08(1)°,V=7.460(5)nm^3,R1=0.0727,wR2=0.1903.结构分析表明,[CrMo6O24H6]^3-阴离子通过端氧担载一个配位的Pr^3+离子形成中性的(C6H5NO2)Pr(H2O)4(CrMo6O24H6)基团,相邻的中性基团在O1-Pr-O1桥联下形成一维链,链与链又通过异烟酸的桥联形成二维层状结构. 相似文献
17.
I. V. Shchirina-Eingorn L. N. Novikova N. A. Ustynyuk L. I. Denisovich M. G. Peterleitner 《Russian Chemical Bulletin》1996,45(7):1608-1610
The roe of oxidatively induced homolyhc scission a the C(sp3)-H bonds in the iron phenykychhexadienyl complexes Fe(5-6-PhC6H6)(5-C5H5) (1) depends on the spatial orientation of the Ph substitutent. In the case of the (1
endo
+) radical cation this process, resulting in the cationic biphenyl complex (Fe(6 -C6H5C6H5)(5-C5H5)]+ (2
+), is fast and proceeds for several minutes. In the case of the more stable radical cation (1
exo
+) the formation of 2+ is slow and takes tens minutes to complete.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1698–1700, July, 1996. 相似文献
18.
《Solid State Sciences》2001,3(7):783-788
The synthesis and structural characterization of the complex [Ru(η6-C6H6)(η6-C6H4(CH3)COOCH3)] [BF4]2 (2) and of its precursor [Ru(η6-C6H4(CH3)COOCH3)Cl2]2 (1) are reported. Compound (2) has been characterized in two polymorphic modifications (2a and 2b) and the molecular organization in the solid state has been investigated. The complex [Ru(η5-C5H5)(η6-C6H5OH)][PF6] (3) has also been investigated; it has been shown to possess a disorder similar to that observed in the high temperature phase of related systems such as [Ru(η5-C5H5)(η6-C6H6)][PF6]. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(6):1058-1067
Three new B-Anderson type polyoxometalates, [(C6H5NO2)2Ln(H2O)6](CrMo6O24H6)·2C6H5NO2·6H2O (Ln?=?Sm 1, Dy 2 and Er 3), have been synthesized in aqueous solution and structurally characterized by single-crystal X-ray diffraction, IR spectra, UV spectroscopy, and fluorescence spectroscopy. Crystal structure analysis reveals that these three compounds have the same composition and are isostructural, assembled by B-Anderson type polyoxoanion [CrMo6O24H6]3?, rare-earth ions, and ligands. UV spectroscopy shows that 1 is stable when pH is 4.50–5.83. The fluorescence spectra of 2 indicate that both rare-earth ions Dy3+ and pyridine-4-carboxylic acid ligands function in the charge transition of the compound. 相似文献