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1.
本文用自洽场组态相互作用方法(SCF-CI)精确计算了次氯酸分子HOCl的振动激发态的能级以及次氯酸分子中的H和Cl分别被D和^3^7Cl取代后的HO^3^7Cl,DO^3^5Cl和DO^3^7Cl的同位素效应, 这些理论计算值与已有的实验结果吻合较好, 还预测了一些尚未观测到的谱线频率及同位素效应。  相似文献   

2.
The structures of several naphthalene derivatives and their35Cl NQR spectra have been investigated. 1,8-Diaminonaphthalene,C 2v 9 -Pna2 1, Z = 8,a (in pm) = 881,b = 1577,c = 1213; 1,8-diaminonaphthalene monodichloroacetate,C 2h 6 -C2/c, Z = 8,a = 2050,b = 584,c = 2333, (in degrees) = 110.1; 1,8-diaminonaphthalene monotrichloroacetate,C 1 1 -P¯1, Z=2,a=1211,b=1062,c=589,=74.8,=80.1,=70.9; 1-aminonaphthalene trichloroacetate,D 2h 15 -Pbca, Z=8,a=2347,b=1289,c=889. The35Cl NQR spectrum of 1,8-diaminonaphthalene monodichloroacetate is a doublet, the frequencies decreasing with increasing temperature from 77 to 217 K at which temperatureT b the NQR signals bleach out. A35Cl NQR triplet is found for 1,8-diaminonaphthalene monotrichloracetate in the range 77 77K 207 (=T b ). 1-Amino-naphthalene trichloroacetate shows a35Cl NQR triplet, too, withT b = 136 K. Characteristic for the intermolecular interactions are hydrogen bonds in the chloroacetic acid salts; each NH3 group forms three hydrogen bonds, and of the two oxygens one is involved in two such bonds, one in one bond. Thereby units of two cations and two anions are formed, and these dirners are connected to strings by hydrogen bonds. Additional van der Waals interactions between the chlorine atoms and the naphthalene ring system are observed. Comparison of the intramolecular bond distances C(i)-C(j) of the C10 naphthalene skeleton for 41 naphthalene derivatives (present data and literature) shows that the bond distances C(i)-C(j)are little influenced by substitution, as is the mean bond length. Shorter and longer distances prove a partial localization of charge at C(1)-C(2), C(3)-C(4), C(5)-C(6), and C(7)-C(8). Regularities within the bond angles and characteristic influences of 1,8-disubstitution on it are discussed.  相似文献   

3.
[ZnCl(2)(3,4,5-trichloropyridine)(2)] features short intermolecular Cl···Cl contacts between halogen atoms of different nature, and a charge density study provides experimental evidence for the accepted model of the halogen bonds: an arene-bonded Cl atom acts as a donor of electron density towards the "sigma hole" of a chlorido ligand attached to a neighbouring Zn(II) cation.  相似文献   

4.
PreparahonofsomecomplexcomPOundsof[Pd(NH3)41X2tw,tvhereX=Cl-,Br,I-,X2=Co,:-,RdChl'-,etc.,wasdescribedasearlyl942l'].SynthesisandcryStalstIUCtUreOfthesaltSt'ithamons,Cr2o7",Cro.:',MoO"',andC,o'=',ttcrestillreportedmorcrecenh/'-'j.IPd(NH)4lX2,tvhereX=Cl',BrandNOz,isanotherkindofamndnepalladiumcomplexcompounds.IntheSyStemofIPd(NH).1"-Cl'-H2o,diamlltinedichloridepalladium(II)wasObtalnedbythereachonOfIPd(NH)4lHcomplexionwtthanutebydrogenchloride,andtetrachloridepalladiumaDbythe…  相似文献   

5.
The reaction of K2[Ru(NO)Cl5] with pyridine in aqueous ethanol at pH ~ 7–8 affords a nitrosoruthenium hydroxocomplex mer-[Ru(NO)Py3Cl(OH)]Cl·1.5H2O (I) (yield ~55%). Treatment of hydroxocomplex I with hydrochloric acid at room temperature gives the aqua complex mer-[Ru(NO)Py3Cl(H2O)]Cl2·2H2O·0.5HCl (II). The structures of the compounds are determined by X-ray crystallography: I, space group P21/n, a = 9.2292(4) Å, b = 11.7781(4) Å, c = 17.4915(7) Å, β = 90.9560(10)°, R = 4.84%; II, space group P-1, a = 7.3528(9) Å, b = 11.5793(11) Å, c = 13.6961(16) Å, α = 84.558(3)°, β = 87.668(4)°, γ = 74.146(4)°, R = 6.22%. Compounds I and II are characterized by powder XRD, 1H and 13C NMR, and IR spectroscopy. The thermal decomposition of compound II in the inert atmosphere is examined by thermal analysis.  相似文献   

6.
在B3LYP/6-31G(d,p)水平上优化了Cl原子与CH3COCH2Cl反应的各驻点的几何构型,并在相同水平上通过频率计算和内禀反应坐标(IRC)分析对过渡态的结构和反应物、产物的连接性进行了验证。采用高精确模型G3MP2方法进行单点能计算,构建了反应的势能剖面。计算结果表明,标题反应有抽氢反应、加成-消除反应、取代反应3种反应机理6条反应通道。利用经典过渡态理论(TST)和正则变分过渡态理论(CVT)计算了各反应通道在200~2000 K温度范围内的速率常数,并用小区率隧道效应模型(SCT)对抽氢反应进行校正。计算结果显示,反应有一定的变分效应,计算的总反应速率常数与文献报道的实验值符合得较好,速率常数的三参数表达式为k=2.33×10-19T2.54exp(567.07/T)cm3·mol-1·s-1。  相似文献   

7.
MP2 calculations with cc-pVTZ basis set were used to analyze intermolecular interactions in F(3)CX···HMgH···Y and F(3)CX···Y···HMgH triads (X = Cl, Br; Y = HCN, and HNC) which are connecting with three kinds of unusual weak interactions, namely halogen-hydride, dihydrogen, and σ-hole. To understand the properties of the systems better, the corresponding dyads are also studied. Molecular geometries, binding energies, and infrared spectra of monomers, dyads, and triads were investigated at the MP2/cc-pVTZ computational level. Particular attention is given to parameters such as cooperative energies, cooperative dipole moments, and many-body interaction energies. Those complexes with simultaneous presence of a σ-hole bond and a dihydrogen bond show cooperativity energy ranging between -1.02 and -2.31 kJ mol(-1), whereas those with a halogen-hydride bond and a dihydrogen bond are diminutive, with this energetic effect between 0.1 and 0.63 kJ mol(-1). The electronic properties of the complexes have been analyzed using the molecular electrostatic potential (MEP), the electron density shift maps, and the parameters derived from the atoms in molecules (AIM) methodology.  相似文献   

8.
The crystal structure of double complex salt [Pt(NH3)5Cl][ReCl6]Cl·H2O is determined. Crystallographic characteristics are: a = 23.9502(4) Å, b = 7.5963(1) Å, c = 8.9016(2) Å, V = 1619.49(5) Å3, space group Pnma, Z = 4, d x = 3.150 g/cm3. The packing of structural fragments is studied. It is shown that on heating the salt in a helium atmosphere up to 840 °C a mixture of two solid solutions of fcc Pt0.90Re0.10 and hcp Pt0.25Re0.75 forms.  相似文献   

9.
The experimental charge density distribution in three compounds, 2-chloro-3-quinolinyl methanol, 2-chloro-3-hydroxypyridine, and 2-chloro-3-chloromethyl-8-methylquinoline, has been obtained using high-resolution X-ray diffraction data collected at 100 K based on the aspherical multipole modeling of electron density. These compounds represent type I (cis), type I (trans), and type II geometries, respectively, as defined for short Cl···Cl interactions. The experimental results are compared with the theoretical charge densities using theoretical structure factors obtained from a periodic quantum calculation at the B3LYP/6-31G** level. The topological features derived from the Bader's theory of atoms in molecules (AIM) approach unequivocally suggest that both cis and trans type I geometries show decreased repulsion, whereas type II geometry is attractive based on the nature of polar flattening of the electron density around the Cl atom.  相似文献   

10.
1D helical channels can be created by "sticky" end-mediated formation of 1D helical stacks composed of short cavity-containing helices and are able to host 1D chains of dichloromethane molecules containing extraordinarily short intermolecular Cl···Cl contacts of 2.524 ? in length that computationally destabilize the host-guest complex by 14.94 kcal mol(-1).  相似文献   

11.
The complex Re2Cl6(P-n-Bu3)2 prepared in situ reacts with CH3CN to form a blue-green solution. Addition of the chelating phosphine bis(diphenylphosphino)methane (dppm) results in the formation of the complex [Re2Cl3(-dppm)2(NCCH3)2][Cl] (1) upon heating. The two acetonitrile molecules adopt a trans geometry on the rhenium center with the axially coordinated chlorine. The analogous trans benzonitrile species [Re2Cl3(-dppm)2(NCC6H5)2][Cl]·2CH2Cl2 (2) is synthesized under the same reaction conditions. The coupling constants of the AABB 31P{1H} NMR spectra of the compounds were elucidated from 31P–31P homonuclear J-resolved NMR experiments. Additional characterization methods include 31P{1H} NMR spectroscopy, UV-vis spectroscopy, and X-ray crystallography.  相似文献   

12.
马咏梅  王艳丽 《化学通报》2014,77(6):539-544
在B3LYP/6-31G(d,p)水平上优化了Cl原子与CH3COCH2Cl反应的各驻点的几何构型,并在相同水平上通过频率计算和内禀反应坐标(IRC)分析对过渡态的结构和反应物、产物的连接性进行了验证。采用高精确模型G3MP2方法进行单点能计算,构建了反应的势能剖面。计算结果表明,标题反应有抽氢反应、加成-消除反应、取代反应3种反应机理6条反应通道。利用经典过渡态理论(TST)和正则变分过渡态理论(CVT)计算了各反应通道在200~2000 K温度范围内的速率常数,并用小区率隧道效应模型(SCT)对抽氢反应进行校正。计算结果显示,反应有一定的变分效应,计算的总反应速率常数与文献报道的实验值符合得较好,速率常数的三参数表达式为k=2.33×10-19T2.54exp(567.07/T)cm3·mol-1·s-1。  相似文献   

13.
采用精密绝热量热计测定了稀土氨基酸配合物[Sm(Val)Cl3·6H2O]在80-376 K温区的热容, 从实验热容值计算出了热力学函数(HT-H298.15和ST-S298.15). 在308 K附近, 配合物的热容出现一个大的跳跃, 可能是其玻璃化转变所致. 对该配合物进行热重测试, 得到了其可能的分解机理.  相似文献   

14.
Sm(Val)Cl3·6H2O低温热容及热化学性质   总被引:3,自引:0,他引:3  
采用精密绝热量热计测定了稀土氨基酸配合物[Sm(Val)Cl3·6H2O]在80-376 K温区的热容,从实验热容值计算出了热力学函数(HT-H298.15和ST-S398.15).在308 K附近,配合物的热容出现一个大的跳跃.可能是其玻璃化转变所致.对该配合物进行热重测试,得到了其可能的分解机理.  相似文献   

15.
1 INTRODUCTION The binuclear complexes have been widely studied in many fields, such as catalysis, semi- conductor and bioinorganic chemistry because of their rich physical and chemical properties[1~4]. The complexes with N-P-tolysulonyl--amino acids ha…  相似文献   

16.
FewcompoundswithMninthe 5oxidationstatewerestructuraIlycharacterizedsofaLC.L.HilIlfirstdeterminedthecrystalstructUreoftheMn(V)complex:NMnTpMPP-Nitriodotrtrakis(p-methoxyphenyl)porphinnato-manganese(V).Thepapers'-'reportedseveralnovelmanganese(V)and(Vl)complexes.RecentpublicationshavebeenestablishedthatthecoordinationcompoundsofhighvaIentmanganesedisplaymanyinterestingfeatures.Theyshowabilitytoundergointramolecularinterligandormetal-ligandelectrontransferreaction,especiallyonthenatUreo…  相似文献   

17.
One of the products of the reaction between Re3S7Br7 and PPh3 has been isolated in crystalline state and characterized by single crystal X-ray diffraction (XRD), mass-spectrometry, and EPR spectroscopy. The crystalline phase obtained is a co-crystallization product of two cluster complexes: [Re33-S)2(μ-S)2(μ-Br)Br3(PPh3)3] (1a) an [Re33-S)2(μ-S)(μ-Br)2Br3(PPh3)3] (1b). The ratio 1a:1b in the investigated single crystal sample is ~7:3.  相似文献   

18.
对苯磺酰牛磺酸阴离子一维链构筑的三维配位聚合物[Cu(phen)2·Cl]·Bsesa(phen=o-phenanth-roline,BsesaH=2-Benzenesulfonylamino-ethanesulfonicacid)进行了元素分析、红外光谱、X射线衍射等表征。分析结果表明此配合物属单斜晶系,空间群为P21/c,晶胞参数为:a=0.9719(2)nm,b=2.5521(5)nm,c=1.2505(2)nm,β=93.407(5)°,V=3.096(1)nm3,Z=4,Dc=1.553g/cm3,μ=0.978mm-1,F(000)=1484。配合物中的金属铜离子与2个邻菲咯啉配位,还与一个Cl阴离子配位。苯磺酰牛磺酸阴离子通过N-H…O氢键形成一维螺旋链,配阳离子通过π-π堆积作用形成一维链,邻近的一维链再通过π-π堆积作用形成二维网,在二维网之间平衡插入由苯磺酰牛磺酸阴离子构筑一维螺旋链,邻近的螺旋链之间的距离为0.972(1)nm,螺旋链与二维网之间通过弱而丰富的C-H…O氢键形成三维网结构。  相似文献   

19.
The free-energy profile for the Menshutkin-type reaction NH3 + CH3Cl → NH3CH3 + + Cl in aqueous solution is studied using the RISM-SCF method. The effect of electron correlation on the free-energy profile is estimated by the RISM-MP2 method at the HF optimized geometries along the reaction coordinate. Solvation was found to have a large influence on the vibrational frequencies at the reactant, transition state and product; these vibrational frequencies are utilized to calculate the zero-point energy correction of the free-energy profile. The computed barrier height and reaction exothermicity are in reasonable agreement with those of experiment and previous calculations. The change of solvation structure along the reaction path is represented by radial distribution functions between solute-solvent atomic sites. The mechanisms of the reaction are discussed from the view points of solute electronic and solvation structures. Received: 26 June 1998/Accepted: 28 August 1998 / Published online: 2 November 1998  相似文献   

20.
采用从头算方法,对多通道反应体系Cl+CH3OCl的反应机理进行了理论研究.在MP2/6-31+G(d,p)水平下优化了反应物、络合物、产物和过渡态的几何构型,并对得到的平衡几何构型进行了简谐振动频率分析.在相同水平下以过渡态为出发点,通过内禀反应坐标(IRC)理论计算了反应的最小能量路径.并且在MC-QCISD(T)/6-31G(d)高水平下进行了单点能量校正.研究结果表明,该反应存在4条可行的反应通道,其中生成HCl和CH2OCl的通道为主反应通道,其他反应通道为次反应通道.  相似文献   

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