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1.
化合物C_(12)H_(10)N_4O_2的合成、晶体结构及量子化学研究   总被引:1,自引:1,他引:0  
以2-吡啶甲酰肼为原料在甲醇和乙酸的混合溶液中合成了标题化合物C_(12)H_(10)N_4O_2。通过采用X射线单晶衍射仪测定了化合物的晶体结构,该晶体属于单斜晶系,空间群为C2/c,晶胞参数为a=1.34782(13)nm,b=1.11699(11)nm,c=0.75678(6)nm,α=90.00°,β=97.7550(10)°,γ=90.00°,V=1.12891(18)nm~2,Z=4,Dc=1.425 Mg.m~(-3),F(000)=504;最终偏差因子R_1=0.0492,wR_2=0.1249[对I>2θ(I)的衍射点]和R_1=0.0659,wR_2=0.1352[对所有衍射点]。该化合物分子由N-N键结合形成直线几何构型,分子间由弱的N—H…O氢键作用形成了二维网状结构。依据晶体结构数据使用程序Guassian 03对化合物进行了量子化学计算,探讨了化合物的分子轨道能量、原子净电荷布居规律和成键特征,分析了其活性原子,并预测了其稳定性。  相似文献   

2.
吡啶-2,6-二甲酸与(n-Bu)2SnO反应合成标题化合物,并经元素分析、IR和X-射线衍射表征,该配合物晶体属四方晶系,空间群P42/n,晶胞参数:a=1.77103(6)nm,b=1.77103(6)nm,c=1.11717(7)nm,α=90°,β=90°,γ=90°,V=3.5041(3)nm3,Z=4,Dc=1.577g/cm3,μ(MoKα)=1.479mm-1,F(000)=1680andR1=0.0329,wR2=0.0852[对I>2σ(I)的衍射]和R1=0.0428,wR2=0.0937(对所有的衍射)。共收集12600个数据,其中独立衍射点3431个,可观察衍射[I>2σ(I)]点2723个用于结构精修。中心Sn原子形成七配位变形十面体,分子间通过氧原子的氢键作用形成三维网络结构。利用量子化学G98W软件,在Lanl2dz基组对化合物的稳定性、前沿分子轨道组成及能量进行研究。  相似文献   

3.
制备苄嘧磺隆的单晶并用X射线衍射测定晶体结构。苄嘧磺隆晶体属于单斜晶系,C2/c空间群。晶胞参数为:a=33.831(7),b=6.902 0(14),c=16.021(3),α=90.00(3)。,β=104.48(3)。,γ=90.00(3)°,V=3 622.1(13)~3。晶体分子内通过N-H…N氢键和C-H…0氢键形成2个六元环,使分子结构较稳定。苯环平面和嘧啶环平面之间的夹角为50.00(15)°。晶体以1中心对称二聚体为基本重复单元。2个分子间以N-H…O氢键和C-H…O氢键连接。晶体由这些二聚体以范德华作用力堆积而成。使用Gaussian 03程序,用B3LYP/6-31G(d,p)法计算分子的优化结构、电荷分布、稳定性、前沿轨道布居分析和3D示意图。算得分子的键长键角数据和X射线衍射的晶体结构数据基本相符。键长和键角的计算值与X射线衍射数据之差证实晶体中分子间的氢键。  相似文献   

4.
吡啶-2,6-二甲酸与(n-Bu)2SnO反应合成标题化合物,并经元素分析、IR和X-射线衍射表征,该配合物晶体属四方晶系,空间群P42/n,晶胞参数:a=1.77103(6) nm,b=1.77103(6) nm,c=l.11717(7) nm,α=90°,β=90°,γ=90°,V=3.5041(3) nm3,Z=4,Dc=1.577g/cm3,μ(MoKα)=1.479mm-1,F(000)=1680 and R1=0.0329,wR2=0.0852[对I> 2σ(I)的衍射]和R1=0.0428,wR2=0.0937(对所有的衍射).共收集12600个数据,其中独立衍射点3431个,可观察衍射[I>2σ(I)]点2723个用于结构精修.中心Sn原子形成七配位变形十面体,分子间通过氧原子的氢键作用形成三维网络结构.利用量子化学G98W软件,在Lan12dz基组对化合物的稳定性、前治分子轨道组成及能量进行研究.  相似文献   

5.
铜(Ⅱ)配合物[Cu(pydc)(H2O)2]2合成、结构和量子化学的研究   总被引:1,自引:1,他引:0  
合成标题配合物[Cu(pydc)(H2O)2]2(pyde=吡啶-2,6-二甲根),经元素分析、IR和X-射线衍射表征,该配合物晶体属三斜晶系,空间群P1,晶胞参数:a=0.47166(11)nm,b=0.8973(2)nm,c=1.0337(2)am,α=81.120(3)°,β=85.755(3)°,γ=83.352(3)°,V=0.42865(17)nm3,Z=1,Dc=2.051 g/cm3,μ(MoKα)=25.57 mm-1,F(000)=266,and R1=0.0250,wR2=0.0631[对I>2σ(I)的衍射]和R1=0.0313,wR2=0.0651(对所有的衍射).共收集数据2350个,其中独立衍射点1498个,可观察衍射[I>2σ(I)]点1311个用于结构精修.中心Cu原子与配基原子形成变形四棱锥,分子间通过氢键作用形成三维网络结构.利用量子化学G98W程序,在Lanl2dz基组研究配合物的稳定性、前沿分子轨道组成及能量.  相似文献   

6.
二正丁基氧化锡和2-氯-3-吡啶甲酸反应,合成2-氯-3-吡啶甲酸二正丁基锡配合物{[n-Bu2Sn(O2CC5H3NCl]2O}2.经X-射线衍射法测定了晶体结构.晶体属三斜晶系,空间群P-1,晶体学参数a=1.17841(9)nm,b=1.20811(9)nm,c=2.7460(2)nm,α=80.5330(10)°,β=84.1140(10)°,γ=64.2450(10)°,Z=2,V=3.4709(5)nm3,Dc=1.521 mg·m-3,μ(MoKa)=1 628 mm-1,F(000)=1592,R1=0.0430,wR2=0.1005.化合物是以Sn2O2构成的平面四元环为中心环的二聚体结构,锡原子均为五配位的畸变三角双锥形.用量子化学从头计算其结构,探讨配合物的稳定性、分子轨道能量以及一些前沿分子轨道的组成特征.  相似文献   

7.
以异烟酸和1,10-邻菲啰啉为配体通过水热反应合成了化学合物Mn(C6H4O2N)2(H2O)4,首次用X-射线单晶衍射仪测定了其晶体结构,同时使用G03程序对该化合物进行了量子化学计算,探讨了化合物的Wiberg键级、电荷布居及前线分子轨道的能量、原子轨道布居规律.结果表明:该晶体属三斜晶系,空间群P(1),晶胞参数为:a=0.6347(3)nm,b=0.6922(3)nm,c=0.9286(4)nm,α=96.226(7)°,β=104.929(6)°,γ=112.939(6)°,V=0.352 9(3)nm3,Dc=1.747 g/cm3,Z=1,F(000)=191.最终偏离因子R1=0.045 7,wR2=0.1368.在标题化合物中2个异烟酸根的2个氮原子及4个水分子与Mn(Ⅱ)配位,形成了六配位的变形八面体结构.标题化合物的总能量为-688.647 2 au,最高占据轨道HOMO的能量为-0.296 57 a.u,最低空轨道LUMO的能量为-0.00904 a.u,两前沿轨道的能量间隙为0.305 61 a.u.其能级间隙值较大,说明标题化合物基态的稳定性较好;同时其Wiberg键级及电荷布居的数据与晶体测试结果相吻合,表明理论化学的方法应用于该化合物结构的研究较令人满意.  相似文献   

8.
在甲苯溶剂中以蒽和顺丁烯二酸酐为原料合成了标题化合物C36H24O6,并测定了化合物的晶体结构,该晶体属单斜晶系,空间群P2(1)/c,晶胞参数为:a=1.1255(3)nm,b=0.9482(2)nm,c=1.2894(3)nm,β=103.563(4)°,V=1.3376(5) nm3,Dc=1.372 g/cm3,Z=2,F(000)=576。最终偏离因子R1=0.0436,wR2=0.0886。依据晶体结构数据使用G03程序对化合物进行了量子化学计算,探讨化合物的稳定性、分子轨道能量、原子净电荷布居规律。  相似文献   

9.
用水杨酸甲酯和水合肼、丙酮在甲醇水混合溶液中合成了标题化合物C10H14N2O3,并测定了其晶体结构,该晶体属单斜晶系,空间群P2(1)/n,晶胞参数为:a=0.482 71(15)nm,b=1.560 5(5)nm,c=1.420 8(4)nm,β=90.899(6)°,V=1.070 1 (6)nm3,Dc=1.305g/cm3,Z=4,F(000)=448。最终偏离因子R1=0.047 2,wR2=0.104 3。依据晶体结构数据使用G03程序对化合物进行了量子化学计算,得到了其分子轨道能量和原子净电荷布居规律,分析了其活性原子,并预测了其稳定性,为研究标题化合物异丙基水杨酰腙的生物活性、配合物的合成提供理论指导。  相似文献   

10.
铜(Ⅱ)盐与吡啶-4-甲酸水溶液合成标题配合物,并经元素分析、IR和X-射线衍射表征,该配合物晶体属三斜晶系,空间群P-1,晶胞参数:α=0.6310(3)nm,b=0.6906(3)nm,c=0.9234(6)nm,α=96.312(19)°,β=105.26(2)°,γ=113.353(14)°,V=0.3458(3)nm3,Z=1,Dc=1.824g/cm3,μ(MoKα)=1.627mm-1,F(000)=195,and R=0.0360,wR2=0.1051[对I>2σ(I)的衍射]和R1=0.0361,wR2=0.1051(对所有的衍射).共收集1803个数据,其中独立衍射点1226个,可观察衍射[I>2σ-(I)]点1223个用于结构精修.中心Cu原子关于配基原子形成变形八面锥,分子间通过氢键作用形成三维网络结构.利用量子化学G98W程序,在Lan12dz基组对配合物的稳定性、前沿分子轨道组成及能量进行研究.  相似文献   

11.
通过Cu(ClO4)2和phen(phen=1,10-邻啡罗啉)合成配合物[Cu(phen)2Cl(ClO4)]n,并表征其结构,晶体结构为单斜晶系,空间群为P21/c,晶体学参数:a=1.2666(2)nm,b=1.1219(2)nm,c=1.7225(2)nm,β=111.462(8)°,V=2.2779 (6)nm3,wR=0.071。在晶体中两个邻啡罗啉氮与中心铜离子配位形成2个五元环,4个氮和氯原子与中心铜形成变形四面锥,配合物之间邻近邻啡罗啉的芳环通过π…π作用形成一维结构,通过Cl…H和O…H“氢键”作用形成三维结构,邻近邻啡罗啉的芳环相互平衡组成π…π作用形成一维结构。量子化学(HF/LanL2DZ)计算表明,在配合物中HOMO电子(由铜原子的d轨道、氯和氮的p轨道)向LUMO和LUMO-1(碳原子的p轨道)转移。  相似文献   

12.
A method of controlling anchoring energy of surface interaction of liquid crystal photoaligning substances is considered to enhance the liquid crystal display performances. An important parameter of the dye's molecular structure that determines the ratio of polar and azimuthal anchoring energy is the ability to form dimers. The values of dimerization thermodynamic potentials have been found. The probability of the formation of dye molecules dimers is evaluated. The bonds conjugation transfer via intermolecular hydrogen bond is revealed, and anisotropy of polarizability of the hydrogen bond is evaluated. The effect of dimerization on polar and azimuthal anchoring energy of liquid crystal — azo dye system — is shown.  相似文献   

13.
The title compound, N-3-hydroxyphenyl-4-methoxybenzamide (3) was prepared by the acylation reaction of 3-aminophenol (1) and 4-metoxybenzoylchloride (2) in THF and characterized by 1H NMR, 13C NMR and elemental analysis. Molecular structure of the crystal was determined by single crystal X-ray diffraction and DFT calculations. 3 crystallizes in monoclinic P21/c space group. The influence of intermolecular interactions (dimerization and crystal packing) on molecular geometry has been evaluated by calculations performed for three different models; monomer (3), dimer (4) and dimer with added unit cell contacts (5). Molecular structure of 3, 4 and 5 was optimized by applying B3LYP method with 6-31G+(d,p) basis set in gas phase and compared with X-ray crystallographic data including bond lengths, bond angles and selected dihedral angles. It has been concluded that although the crystal packing and dimerization have a minor effect on bond lengths and angles, however, these interactions are important for the dihedral angles and the rotational conformation of aromatic rings.  相似文献   

14.
A theoretical study to understand the interaction between anion and the water molecules through the hydration (X·(H2O)n (X = OH, NO2, NO3, CO3), where n = 1–10), using the density functional theory method with B3LYP functional and 6-311++G(d,p) basis set has been carried out systematically. In these hydrated clusters we notice three different cases of bond arrangements, namely, symmetrical double hydrogen bond, single hydrogen bond and inter-water hydrogen bond. All the complexes are dominated by the OH⋯O hydrogen bond, in which the anion act as a proton acceptor, while the water molecule act as a proton donor. A linear correlation is obtained between the solvent stabilization energy and the size (n) of the hydrated cluster for all the anions. The weighted average interaction energy values, shows that the water molecules strongly bind with the OH anion. Besides, the solvation of the OH anion requires less number of water molecules when compared with the other anions. Energy decomposition analysis (EDA) shows the strong dominance of the electrostatic energy component within the interaction energy. The total NPA charges on the anions indicate an increase in the solvation due to hydration. From AIM analysis, excellent linear inverse correlation is observed for both the electron density and Laplacian of the electron density with respect to the hydrogen bond length. Natural bonding orbital analysis (NBO) predicts large charge transfer between the OH anion and the water molecules.  相似文献   

15.
受限于平行硅板中水的分子动力学模拟   总被引:1,自引:0,他引:1       下载免费PDF全文
陈博陈云飞  ? 《传感技术学报》2006,19(5):1635-1637
采用分子动力学模拟方法研究了不同间距(16.6,13.6,和11.8 A)两硅平板之间水分子的结构性质,模拟结果显示:受限水呈现出与体态水完全不同的结构性质,即水分子的分布依赖于两板间距.间距为16.6 A时,硅壁的吸引力造成了其附近形成两个明显的水层,其中的水分子的O-H平行于壁面形成氢键.随着间距的减小,第二层水分子中的O-H键由平行于壁面转向垂直于壁面,与临近的水层通过氢键相连.此外,模拟结果表明,在不同上下板间距情况下,被壁面吸引所形成的水层中水分子的结构取向基本没有变化.  相似文献   

16.
Molecular dynamics simulations were performed under conditions of constant volume and temperature and of constant pressure and temperature to elucidate the structure activity relationships of a series of non-ionic surfactant molecules derived from vegetable fat and employed as friction modifiers in commercial engine oils. The simulations show the extent to which intermolecular hydrogen bonding is important in determining the stability of the monolayer formed by the surfactant molecules and show that mono-alkanoyl glyceride molecules are able to pack more efficiently, forming significantly more intermolecular hydrogen bonds and occupying approximately half the volume needed by di-alkanoyl glyceride molecules. Density profiles are presented which show significant mixing of the hydrophobic tail groups and a non-polar solvent. The distribution of torsion angles in the tail groups shows that the conformation is consistent with a liquid at finite temperature rather than a crystal structure. The measured friction coefficients of equimolar solutions of the glycerides show that the efficacy as friction modifiers varies in the order mono-, di- and the tri-oleyl glyceride, which is consistent with the efficacy of film formation predicted by the molecular dynamics calculations.  相似文献   

17.
We present a 250 ps molecular dynamics simulation of the T-antigen Gal beta(1-3)GalNAc and its isomer Gal beta(1-3)GlcNAc in the classic Gibbs Ensemble, Number of particles, Pressure and Temperature (NPT) with explicit representation of 432 water molecules. We computed the radial distribution function, equilibrium conformation, intramolecular and intermolecular hydrogen bonds, and water residence time to characterize the hydration pattern of these sugars, which are not very different and exhibit hydrophilic behavior. Based on hydration dynamics, it was concluded that these sugars should be classified as negative hydrated. Formation of an intramolecular hydrogen bond between the ring oxygen atom O5 of the first unit and the OH4' group of glycoside of the second unit might influence interaction with the antigenic receptor and could explain the main difference of affinities between them.  相似文献   

18.
We have designed and synthesized azo dyes with reversible intermolecular bonds, which can be used as materials for liquid crystal photoalignment. The generation of anisotropic structures in azo dye thin film is possible due to the presence of intermolecular hydrogen or coordination (metal–oxygen) bonds. All thin film materials are resistant to air moisture, while photoalignment material with reversible hydrogen bonds is inert to direct water contact. In this paper, we study photoalignment dynamics of obtained materials and discuss possible formation of intramolecular and intermolecular hydrogen bonds within the photoalignment dye layer.  相似文献   

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