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1.
采用B3LYP/6-31G*方法, 对内含式化合物X@Al12P12 (X=Li0/+, Na0/+, K0/+, Be0/2+, Mg0/2+, Ca0/2+, H和He)的不同对称性构型进行计算, 讨论其最稳定构型的几何参数、布居分析、偶极矩、电离势、包含能、频率、HOMO-LUMO能隙和自旋密度.发现X@Al12P12化合物中, 客体X=Na0/+, K0/+, Mg和He几乎处在笼的中心, Be和Ca0/2+处在中心附近0.033 nm的半径内, Li0/+, Be2+, Mg2+和H很大程度上偏离笼的中心位置. 大部分金属内含式化合物的C3对称性构型稳定.Li0/+, Be0/2+, Mg2+, Ca2+和H与其它离子相比更易嵌入笼内形成稳定的内含式化合物. 相似文献
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内含式化合物X@Al12P12的结构与稳定性研究 总被引:1,自引:0,他引:1
采用B3LYP/6—31G*方法,对内含式化合物X@Al12P12(X=Li^0/ ,Na^0/ ,K^0/2 ,Be^0/2 ,Mg^0/2 ,Ca^0/2 ,H和He)的不同对称性构型进行计算,讨论其最稳定构型的几何参数、布居分析、偶极矩、电离势、包含能、频率、HOMO—LUMO能隙和自旋密度.发现X@Al12P12化合物中,客体X=Na^0/ ,K^0/ ,Mg和He几乎处在笼的中心,Be和Ca^0/2 处在中心附近0.033nm的半径内,Li^0/ ,Be^2 ,Mg^2 和H很大程度上偏离笼的中心位置.大部分金属内含式化合物的C3对称性构型稳定.Li^0/ 。,Be^0/2 ,Mg^2 ,Ca^2 和H与其它离子相比更易嵌入笼内形成稳定的内含式化合物. 相似文献
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采用B3LYP/6-31G*方法,对内含式化合物X@B12P12(X=Li0/+、Na0/+、K0/+、Be0/2+、Mg0/2+、Ca0/2+、H和He)的不同对称性构型进行了计算,讨论其最稳定构型的几何参数、布居分析、偶极矩、电离势、包含能、振动频率、能隙和自旋密度. 发现在X@B12P12化合物中,客体X=Li、Na0/+、K0/+、Mg0/2+、Ca0/2+和He处在偏离笼的中心0.006 nm的半径内. Be2+沿着C3轴偏离中心点0.279 nm. 在Be@B12P12和H@B12P12的基态结构中,Be和H与笼上的B原子成键. 除Li@B12P12、 Be2+@B12P12和He@ B12P12外, 其余结构为Cs对称稳定构型. 相似文献
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Using quantum chemistry methods B3LYP/6-31++G(d,p) to optimize endohedral complexes X@(HBNH)12 (X=Li^0/+, Na^0/+, K^0/+, Be^0/2+, Mg^0/2+, Ca^0/2+, H and He), the geometries with the lowest energy were achieved. Inclusion energy, standard equilibrium constant, natural charge, spin density, ionization potentials, and HOMO-LUMO energy gap were also discussed. The calculation predicted that X=Na^0/+, K^0/+, Mg^0/2+, Ca^0/2+, H and He are nearly located at the center of (HBNH)12 cluster. Li^+ lies in less than 0.021 nm departure from the center. Li and Be^0/2+ dramatically deviate from the center. (HBNH)12 prefers to enclose Li^+, Be^2+, Mg^2+, and Ca^2+ in it than others. Moreover, M@(HBNH)12 (M=Li, Na, K) species are "superalkalis" in that they possess lower first ionization potentials than the Cs atom (3.9 eV). 相似文献
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用DFT的B3LYP方法在6-31G(d)基组的水平上, 对闭式多面体簇合物(HAlNH)12及其内含式X@(HAlNH)12和外接式X(HAlNH)12 (X=F-, Cl-, Br-, O2-, S2-, Se2-)复合物的结构进行了构型优化和能量计算, 并讨论了几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系, 最后得到复合物结构的稳定性信息, 具有Th对称性的X@(HAlNH)12 (X=F-, Cl-, Br-, S2-, Se2-)复合物和具有C3对称性的O2-@(HAlNH)12复合物为内含式的基态结构, 从能量角度分析, 内含式复合物比外接式复合物的结构稳定. 相似文献
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用DFT的B3LYP方法在6-31G(d)基组的水平上, 对闭式多面体簇合物(HAlNH)12及其内含式X@(HAlNH)12和外接式X(HAlNH)12 (X=F-, Cl-, Br-, O2-, S2-, Se2-)复合物的结构进行了构型优化和能量计算, 并讨论了几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系, 最后得到复合物结构的稳定性信息, 具有Th对称性的X@(HAlNH)12 (X=F-, Cl-, Br-, S2-, Se2-)复合物和具有C3对称性的O2-@(HAlNH)12复合物为内含式的基态结构, 从能量角度分析, 内含式复合物比外接式复合物的结构稳定. 相似文献
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在研究闭式多面体(HAlNH)12簇合物几何构型及稳定性的基础上, 用DFT的B3LYP方法在6-31G(d)的水平上, 对其内含式复合物X@(HAlNH)12 (X= Be, Mg, Ca, Zn, Al+, Ga+)进行了构型优化和能量计算, 并讨论了稳定结构的几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系. 用Gaussian 03的QST3方法确定了客体X通过笼面6-元环的迁移过渡态(TS)结构, 并用IRC方法对所得TS结构进行了验证. 最后得到内含式复合物X@(HAlNH)12结构在热力学和动力学上的稳定性信息, 其中复合物Ga+@(HAlNH)12的结构相对最稳定. 相似文献
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在研究闭式多面体(HA1NH)12簇合物几何构型及稳定性的基础上,用DFT的B3LYP方法在6-31G(d)的水平上,对其内含式复合物X@(HAINH)12(X=Be,Mg,Ca,Zn,Al ,Ga )进行了构型优化和能量计算,并讨论了稳定结构的几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系.用Gaussian 03的QST3方法确定了客体X通过笼面6-元环的迁移过渡态(TS)结构,并用LRC方法对所得TS结构进行了验证.最后得到内含式复合物X@(HA1NH)12结构在热力学和动力学上的稳定性信息,其中复合物Ga @(HAINH)12的结构相对最稳定. 相似文献
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(Nd1-xYx)3Fe27.31Ti1.69化合物的结构与磁性研究 总被引:2,自引:0,他引:2
制备了(Nd1-xYx)3Fe27.31Ti1.69(0≤x≤0.6)系列化合物,通过X射线衍射和磁性测量等手段研究了它们的结构和磁性.这些化合物均为Nd3(Fe,Ti)29型结构,A2/m空间群.化合物晶胞体积随Y含量增加而单调减少,居里温度Tc随Y含量增加略有降低,说明化合物的居里温度主要由Fe-Fe之间的交换相互作用所决定.温度为5K时,饱和磁化强度Ms随Y含量的增加而单调降低,与一个简单的稀释模型预期结果一致.所得化合物在低温下均发生自旋重取向,自旋重取向温度Tsr随Y含量增加而单调降低,从x=0时的232K减小到x=0.6时的121K.基于磁晶各向异性的研究结果确定了所得化合物的自旋相图. 相似文献
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The compound [Mn2(CO)10] reacts with 2-(Methylthio)thiophene (C5H6S2) while refluxing in xylene to afford a methylthio-tetramanganese product [MnS(CO)3]4, in which C5H6S2 is cleaved with loss of thiophene. The crystal structure of [MnS(CO)3]4 has been studied by direct method. Based on the 21 685 unique reflections collected using MoKα of X-ray radiation and a CCD-based detector, it is refined to an agreement index (R1) of 0.079 0. The cell is triclinic with dimensions: a=1.719 49 nm, b=1.959 2 nm, c=2.632 6 nm and α=79.733°, β=71.407°, γ=89.387°. There are 12 unit cells of [MnS(CO)3]4 in the cell, with space group P1. 相似文献
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[Zn(DMF)6]H2SiW12O40·(CH3)2NH的合成,晶体结构及性质 总被引:1,自引:0,他引:1
The title compound [Zn(DMF)6]H2SiW12O40·(CH3)2NH was synthesized in mixed solvent of aqueous and acetonitrile, and its crystal structure had been determined using single crystal X-ray diffraction. The crystal belongs to monoclinic, space group C2/m, a=2.0654(4)nm, b=1.3306(3)nm, c=1.3194(3)nm, β=119.59(3)°, V=3.1531(11)nm3, Dc=3.606Mg·m-3, Z=2, R=0.0462, Rw=0.0836. The title compound comprises of a [Zn(DMF)6]2+ unit, a polyanion and a free (CH3)2NH molecule. The ESR spectrum of the title compound shows that charge-transfer between organic groups and polyanion takes place under irradiation of the sunlight in solid state. The TG study of the title compound shows that it had four stages of the weight loss, and the increase of the de-composition temperature for the polyanion shows that the stability of the polyanion was enhanced due to the influence of Zn2+ ion. CCDC:175866. 相似文献
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用Xα方法计算了Ni(C5H5)2的电子能级与归一化电荷,讨论了夹心化合物成键的特点,并用过渡态方法分析Ni(C5H5)2的光电子能谱及紫外可见吸收光谱,结果与实验相符。 相似文献
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[Cu(TO)2(H2O)4](PA)2 was prepared by the reaction of aqueous 1,2,4-triazol-5-one (TO) solution with the solution of copper picrate Cu(PA)2 and characterized by elemental analysis, FT IR and X-ray powder diffraction analysis. The title complex has been studied by means of TG-DTG and DSC under conditions of linear temperature increase. The thermal decomposition residues were examined by FT IR analysis. Thermal decomposition mechanism of the title complex was proposed. In the temperature range of 30-680 ℃, the thermal decomposition process was composed of four major stages. The first stage was an endothermic process with the loss of four coordination water molecules. Since the dehydration product was unstable, when it was heated, it would be decomposed much more easily. The second stage was composed of an acute endothermic process and a continued strong exothermic process and the main decomposed residues were CuCO3, Cu(NCO)2 and polymers during this stage. The third stage was a sharp exothermic process, which resulted from the decomposition of the polymer. After the forth stage, the final decomposed residues were certainly copper oxide. The Arrhenius parameters have been also studied on the dehydration process and the first-step exothermic decomposition of [Cu(TO)2(H2O)4](PA)2 using Kissinger's method and Ozawa-Doyle's method. The results using both methods were consistent with each other. The Arrhenius equation can be expressed as in k=24.0-179.8 × 10^3/RT for the dehydration process and in k= 16.7-206.0 × 10^3/RT for the first-step exothermic decomposition, on the basis of the average of Ea and In A through the two methods. 相似文献
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Structures and thermodynamic properties of the imidoboranes (HBNH)n (n=1-16) have been investigated theoretically at the B3LYP/6-31G^* level of theory. Needle-shaped oligomers that violate the isolated square rule were found to be more stable than cage isomers. The needle-shaped oligomer with n=16 was predicted to be exceptionally stable at low temperature, hexamer and octamer clusters dominated the gas phase at higher temperature. The highest oligomerization degree of the spontaneous cluster fomation has been estimated. It was concluded that generation of the gas phase (HBNH)n clusters with oligomerization degree n ≥24 was viable, making these species possible intermediates involved in the gas phase generation of BN nanoparticles. 相似文献
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用DFT的B3LYP方法在6-31G(d)基组的水平上,对闭式多面体簇合物(HA1NH)12及其内含式X@(HA1NH)12外接式X(HA1NH)12(X=F-,Cl-,Br-,O2-,S2-,Se2-)复合物的结构进行了构型优化和能量计算,并讨论了几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系,最后得到复合物结构的稳定性信息,具有Th对称性的X@(HA1NH)12(X=F-,Cl-,Br-,S2-,Se2-)复合物和具有C3对称性的O2-@(HA1NH)12复合物为内含式的基态结构,从能量角度分析,内含式复合物比外接式复合物的结构稳定. 相似文献
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A new nickel(Ⅱ)-dicyanamide compound, [Ni(dca)2(en)]n (1) (dca=dicyanamide anion, [N(CN)2]-); en=ethylene diamine), has been synthesized and its structure has been determined by single crystal X-ray diffraction analysis. The crystal is monoclinic, space group P21/n with unit cell dimensions: a=0.694 3(1) nm, b=1.041 5(2) nm, c=1.4132(2) nm, and β=90.381°, Z=4, V=1.011 0(3) nm3. In this compound, the adjacent nickel atoms are connected by dca all in μ1,5-bridging mode to form ladder-like units, which are linked with double dca bridges to generate a regular infinite stair-like structure. Temperature-dependent magnetic susceptibility was also characterized for this compound. CCDC: 208276. 相似文献
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三元混配化合物[Cu(8-Q)2(phen)]·H2O及[Cu(NCS)2(phen)2]·H2O的固相合成 总被引:5,自引:0,他引:5
用室温固相反应合成了[Cu(8-Q)2(phen)]·H2O及[Cu(NCS)2(phen)2]·H2O两个三元混配化合物。室温下[Cu(Ac)2(H2O)]与邻菲啉固体几乎不发生反应,但加入第二配体8-羟基喹啉及KSCN,反应几乎立即发生。XRD、IR谱及元素分析结果表明:第二配体的加入并不仅仅促进[Cu(Ac)2(H2 相似文献
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利用水热合成技术成功制备出一种新型多钒硼氧化合物, 用X射线单晶衍射分析技术对其晶体结构和分子结构进行了确定。结果表明在该化合物中多钒硼氧阴离子具有一个新颖的三明治结构。上下两个结构单元都是由六个VO5四角锥交替地通过顺式和反式共边的方式连接起来构成的一个钒氧三角形结构。中间的结构单元是由BO3平面三角形和BO4四面体以共角的方式相互连接形成的一个折叠型的B18O36(OH)6环。三明治结构中层与层之间通过桥氧相连。一个水分子处于它的核心位置上,与每个VO5四角锥中的钒原子都保持几乎相等的距离。该化合物及其晶体中存在着丰富的化学结构和成键信息,同时也有作为氧化还原反应催化剂的潜能。 相似文献