C36衍生物C36H12和C36X12簇分子的理论研究

采用从虎ＨＦ／ＳＴＯ－３Ｇ方法,对３６及其衍生物Ｃ３６Ｈ１２和Ｃ３６Ｘ１２（Ｘ＝Ｆ,Ｃｌ,Ｂｒ,Ｉ）进行计算研究,讨论了Ｃ３６Ｈ１２和Ｃ３６Ｘ１２簇分子几何结构随卤素Ｘ原子序数变化的规律,分子的稳定性及电荷转移情况,结果表明,Ｃ３６Ｈ１２和Ｃ３６Ｆ１２在所有簇分子中是较为稳定的。     

C28X4（X=H,Cl）,CX4（X=H,Cl）的结构和电子光谱的理论研究

用ＩＮＤＯ法对Ｃ２８Ｘ４（Ｘ＝Ｈ，Ｃｌ）和ＣＸ４（Ｘ＝Ｈ，Ｃｌ）进行几何构型优化，得到Ｔｄ对称性的构型Ｃ２８Ｘ４有４种键、４种不等同原子，基态为稳定的闭壳层分子，以此构型为基础计算了上述分子的电子光谱，并预测Ｃ２８Ｘ４的电子光谱。     

夹心羰基化合物（C5H5）2Ti（CO）2的电子结构及化学键研究

用量子化学从头算方法（ＳＴＯ－３Ｇ基组）对（Ｃ５Ｈ５）２Ｔｉ（ＣＯ）２进行几何优化，得到平衡几何构型，并在此基础上采用ＳＴＯ－３－２１Ｇ基组对（Ｃ５Ｈ５）２Ｔｉ（ＣＯ）２进行单点计算，计算结果表明：（Ｃ５Ｈ５）２Ｔｉ（ＣＯ）２的ＨＯＭＯ具有Ｔｉ→ＣＯ反馈π键性质，理论计算结果与实验相符。     

金属碳笼化学反应的理论研究（Ⅰ）——Ti8C12^＋＋CH3I→Ti…

用量子化学从头计算方法对反应Ｔｉ８Ｃ１２＾＋＋ＣＨ３Ｉ→Ｔｉ８Ｃ１２＾＋－Ｉ＋ＣＨ３·进行了理论研究，对Ｔｉ８Ｃ１２＾＋只能与一个卤素原子结合的实验事实给予了合理的理论解释。     

C12簇及其碳管烷C12H12的理论研究

C60和C70等碳笼烯的发现及其在新物质、新材料等研究领域中的重要性，激励人们去探索合成更多新型多面体碳簇化合物与碳元素类似物[1，2]．最近，两类新型多面体碳管笼烯的设想提出来了[3，4]应用HMO和MNDO方法对其稳定性变化规律、结构和成键特征进行了讨论.关于多苯的vanderWaals簇实验上已有广泛的调查[5，6]，理论上对其二聚物（C6H6）。的不同几何构型与稳定性进行了深入的研究[7]．本文采用abinitio计算有效势（effectivecorePotential）方法，对C12碳管元素簇和C12H12，碳管烷的平衡结构、稳定性和价键特征进行了理论预测．1…     

C59（C6H4CH3）N的结构,UV—VIS光谱,NMR谱以及非线性光学性质的理论 …

用ＩＮＤＯ系列方法对由（Ｃ５９Ｎ）２和甲苯合成的衍生物Ｃ５９（Ｃ６Ｈ４ＣＨ３）Ｎ进行了理论研究，得到了分子的稳定构型，表明Ｃ５９（Ｃ６Ｈ４ＣＨ３）Ｎ具有Ｃｓ对称性。以优化构型为基础讨论了分子的ＵＶ－ＶＩＳ光谱、ＮＭＲ谱，结果瑟实验符合得很好。还计算了Ｃ５９－（Ｃ６Ｈ４ＣＨ３）Ｎ的二阶非线性光学系数βμ，结果表明这种分子具有较大的二阶非线性光学系数。     

C59(C6H4CH3)N的结构、UV-VIS光谱、NMR谱以及非线性光学性质的理论研究

用ＩＮＤＯ 系列方法对由（Ｃ５９Ｎ）２和甲苯合成的衍生物Ｃ５９ （Ｃ６Ｈ４ＣＨ３）Ｎ进行了理论研究,得到了分子的稳定构型,表明Ｃ５９（Ｃ６Ｈ４ＣＨ３）Ｎ具有Ｃｓ对称性。以优化构型为基础讨论了分子的ＵＶ－ＶＩＳ光谱、ＮＭＲ谱,结果与实验符合得很好。还计算了Ｃ５９－（Ｃ６Ｈ４ＣＨ３）Ｎ的二阶非线性光学系数βμ,结果表明这种分子具有较大的二阶非线性光学系数。     

原子簇P12（D3d）的理论研究

利用Ｇａｕｓｓｉａｎ－９２程序在６－３１Ｇ基组下优化Ｐ１２（Ｄ３ｄ）构型，研究了３Ｐ４（Ｔｄ）→Ｐ１２（Ｄ３ｄ）的相对能量，计算结果为△Ｅ＝Ｅｐ１２（Ｄ３ｄ）－３Ｅｐ４（Ｔｄ）＝－７９．８４４ｋＪ／ｍｏｌ，优化Ｐ１２（Ｄ３ｄ）获得的Ｐ－Ｐ键键长接近于实验测得的Ｐ－Ｐ单键键长，并进一步在该基组下计算了Ｐ１２（Ｄ３ｄ）原子簇的振动频率，得到的全部为正频率，表明原子簇Ｐ１２的Ｄ３ｄ构型是位能面上的稳定点     

B8N12簇的结构和振动光谱的理论研究

用量子化学从头计算方法研究Ｂ_８Ｎ_（１２）的几何构型、电子结构和振动光谱，讨论其稳定性和化学反应性质。     

C59（C6H4OCH3）N的结构,光谱和二阶非线性光学性质的理？…

用ＩＮＤＯ系列方法对由（Ｃ５９Ｎ）２和苯甲醚合成的衍生物Ｃ５９（Ｃ６Ｈ４ＯＣＨ３）Ｎ进行了理论研究,得到了分子的稳定构型。结果表明,Ｃ５９（Ｃ６Ｈ４ＯＣＨ３）Ｎ具有Ｃｓ对称性,以优化构型为基础讨论了分子的ＵＶ－Ｖｉｓ光谱、ＮＭＲ谱线数,结果与实验符合得很好,本文还计算了Ｃ５９（Ｃ６Ｈ４ＯＣＨ３）Ｎ的二阶非线性光学系数βμ,结果表明这种物质具有较大的二阶非线性光学系数。     

Antiferromagnetic Stabilization in the Ti8O12 Cluster

Using the evolutionary algorithm USPEX and DFT+U calculations, we predicted a high‐symmetry geometric structure of the bare Ti₈O₁₂ cluster composed of 8 Ti atoms forming a cube, in which O atoms are at midpoints of all of its edges, in excellent agreement with experimental results. Using natural bond orbital analysis, adaptive natural density partitioning algorithm, electron localization function, and partial charge plots, we find the origin of the particular stability of bare Ti₈O₁₂ cluster: unique chemical bonding where eight electrons of Ti atoms interacting with each other in antiferromagnetic fashion to lower the total energy of the system. The bare Ti₈O₁₂ is thus an unusual molecule stabilized by d‐orbital antiferromagnetic coupling.     

Ti8C12H8簇的理论研究

用量子化学从头计算方法, 预测了Ti8C12H8簇的几何结构、电子结构, 分析讨论了该簇的成键和化学反应性质。     

Thermal decomposition of Pr[(C_5H_8NS_2)_3(C_(12)H_8N_2)]

The thermal behavior of the complex Pr[(C5H8NS2)3(C12H8N2)] in a dry nitrogen flow was examined by TG-DTG analysis. The TG-DTG investigations indicated that Pr[(C5H8NS2)3-(C12H8N2)] was decomposed into Pr2S3 and deposited carbon in one step where Pr2S3 predominated in the final products. The results of non-isothermal kinetic calculations showed that the decomposition stage was the random nucleation and subsequent growth mechanism (n = 2/3), the corresponding apparent activation energy ?was 115.89 kJ·mol-1 and the pre-expo-nential constant ln[A/s] was 7.8697. The empirical kinetics model equation was proposed as/(α) =3/2(1-α)[-ln(1-α)]1/3.The X-ray powder diffraction patterns of the thermal decomposition products at 800℃under N2 atmosphere show that the product can be indexed to the cubic Pr2S3 phase. The transmission electron microscopy (TEM) of the final product reveals the particle appearance of a diameter within 40 nm. The experimental results show that the praseodymium sulfide nanocrystal can be prepared from thermal decomposition of Pr[(C5H8NS2)3(C12H8N2)].     

4种C_(12)H_(12)多面体烷振动频率及生成焓的DFT研究

采用密度泛函方法,在B3LYP/D95*水平上对4种C12H12多面体分子的构型进行了全优化,计算了其振动频率及红外吸收强度,并模拟了它们的红外光谱图。采用统计热力学方法,在200～600K的温度范围内,分别计算了立方烷生成这4种C12H12多面体分子的热力学函数。由计算得到的自由能得知,这些分子都比立方烷稳定,因此从热力学角度来说,既然立方烷能够合成,这4种C12H12多面体分子也应该能够合成出来。根据计算得到的热力学函数及立方烷的生成焓,求出了这4种C12H12多面体分子的生成焓。     

C24和B12N12团簇的结构与稳定性

本文采用量子化学密度泛函理论的B3LYP/6-31G*方法,对C24和B12N12团簇的12种异构体进行了优化,并对它们的几何构型、振动频率、核独立化学位移(NICS)和结合能进行了理论探讨, 比较了C24和B12N12团簇结构的稳定性。研究表明:C24团簇的最稳定几何构型为类石墨结构d,B12N12团簇的最稳定结构为4/6笼状结构g。C24异构体的稳定性大小顺序为d > b > f > c > a > e。B12N12团簇异构体稳定性大小顺序为a > f> c> d > e >b。     

金属碳笼(Met-Cars)化学反应的理论研究 2: Ti8C12与H2O,C2H4生成Ti8C12(H2O)8和Ti8C12(C2H4)4反应的ab initio研究

用量子化学从头计算方法, 研究了Ti8C12分别与H2O, C2H4作用形成Ti8C12(H2O)8, Ti8C12(C2H4)4的反应。计算结果表明, 在Ti8C12(H2O)8中, 电子由H2O向Ti8C12转移, 在Ti8C12(C2H4)4中, 电子由Ti8C12向C2H4转移。从Ti8C12生成Ti8C12(H2O)8能量降低, 稳定性增加, 生成Ti8C12(C2H4)4能量升高, 稳定性减小。     

Gas-phase interaction of thiophene with the Ti(8)C(12)(+) and Ti(8)C(12) met-car clusters

The reactivity of the Ti(8)C(12)(+) met-car cation toward thiophene was investigated using density functional theory (DFT) and mass selective ion chemistry. It is shown that the experimentally observed mass spectrum can be well described by the DFT calculations. In contrast to the weak bonding interactions seen for thiophene on a TiC(001) surface, the Ti(8)C(12)(+) met-car cation is able to interact strongly with up to four thiophene molecules with the cluster staying intact. In the most stable conformation, the thiophene molecules bond to the four low-coordinated Ti(0) sites of Ti(8)C(12)(+) via a eta(5)-C,S coordination. The stability and the activity of the Ti(8)C(12)(+) met-car is observed to increase with an increasing number of attached thiophene molecules at the Ti(0) sites, which is associated with a significant transfer of electron density from thiophene to the cluster. The additional electron density on the Ti(8)C(12)(+) cation cluster, however, is not sufficient to cleave the C-S bonds of thiophene and the dissociation reaction of thiophene is predicted to be a highly activated process. By contrast, DFT calculations for the neutral Ti(8)C(12) met-car predict that the dissociation reaction leading to adsorbed S and C(4)H(4) fragments is energetically favorable for the first thiophene molecule. The binding behavior for subsequent addition of thiophene molecules to the neutral met-car is also presented and compared to that of the cation.     

Theoretical studies on the electronic structure of Ti8C12 isomers

Density functional calculation are performed to study Ti(8)C(12) isomers (T(d), C(3v), and D(2d)) in the neutral, cationic, and anionic charge states. C(3v) symmetry is found to be the most stable geometry for the neutral and anion, and the C(3v) and D(2d) isomers to be quasi-iso-energetic lowest for the cation. The electronic structure analysis show that d electron tends to be localized in the ground state. The theoretical assignment for the features in the experimental photoelectron spectra is given. All results obtained are in good agreement with the available experimental data and indicate that the C(3v) and D(2d) isomers may coexist in the photoelectron spectroscopy experiment.     

反应气氛对Li4Ti5O12/C复合材料性能的影响研究

以葡萄糖为碳源,采用固相法制备了Li4Ti5O12/C复合材料。探讨了不同反应气氛（N2/O2）对材料物理性质及电化学性能的影响,并通过XRD、BET、电导率、电性能等测试手段对其进行表征。结果表明：氮气气氛中烧结的样品粒度、比表面积、电导率均比空气中烧结样品大。氮气中烧结样品的倍率性能优于空气中 烧结样品,在以0.1C倍率充放电时,首次放电比容量为166.8mAh/g。两样品1C时,经过50次循环容量保持率差别不大。