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金属富氮化合物N_3MN_3(M=Be,Mg,Ca)的量子化学研究 被引量:7
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作者 段红霞 李前树 《分子科学学报》 CAS CSCD 2005年第6期56-59,共4页
使用密度泛函理论,在B3LYP/6-311+G*水平上,对金属富氮化合物N3MN3(M=Be,Mg,Ca)的两种几何结构进行了理论计算,并对得到的几何结构做了振动频率分析.结果表明,所有几何结构的振动频率都是正的,没有虚频存在,说明这类金属富氮化合物是热... 使用密度泛函理论,在B3LYP/6-311+G*水平上,对金属富氮化合物N3MN3(M=Be,Mg,Ca)的两种几何结构进行了理论计算,并对得到的几何结构做了振动频率分析.结果表明,所有几何结构的振动频率都是正的,没有虚频存在,说明这类金属富氮化合物是热力学稳定的,当嵌入金属离子后,M—N之间开始表现出显著的离子性特征,由线形N3基团组成的N3MN3比由三角形N3基团组成的N3MN3更稳定. 展开更多
关键词 金属富氮化合物 B3LYP 振动频率 nbo分析
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Theoretical study of the N—H···O red-shifted andblue-shifted hydrogen bonds 被引量:6
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作者 YANG Yong ZHANG WeiJun +3 位作者 PEI ShiXin SHAO Jie HUANG Wei GAO XiaoMing 《Science China Chemistry》 SCIE EI CAS 2007年第1期32-40,共9页
Theoretical calculations are performed to study the nature of the hydrogen bonds in complexes HCHO···HNO, HCOOH···HNO, HCHO···NH3, HCOOH···NH3, HCHO·... Theoretical calculations are performed to study the nature of the hydrogen bonds in complexes HCHO···HNO, HCOOH···HNO, HCHO···NH3, HCOOH···NH3, HCHO···NH2F and HCOOH···NH2F. The geomet- ric structures and vibrational frequencies of these six complexes at the MP2/6-31+G(d,p), MP2/6-311++G(d,p), B3LYP/6-31+G(d,p) and B3LYP/6-311++G(d,p) levels are calculated by standard and counterpoise-corrected methods, respectively. The results indicate that in complexes HCHO···HNO and HCOOH···HNO the N—H bond is strongly contracted and N—H···O blue-shifted hydrogen bonds are observed. While in complexes HCHO···NH3, HCOOH···NH3, HCHO···NH2F and HCOOH···NH2F, the N—H bond is elongated and N—H···O red-shifted hydrogen bonds are found. From the natural bond orbital analysis it can be seen that the X—H bond length in the X—H···Y hydrogen bond is controlled by a balance of four main factors in the opposite directions: hyperconjugation, electron density redistribu- tion, rehybridization and structural reorganization. Among them hyperconjugation has the effect of elongating the X—H bond, and the other three factors belong to the bond shortening effects. In complexes HCHO···HNO and HCOOH···HNO, the shortening effects dominate which lead to the blue shift of the N—H stretching frequencies. In complexes HCHO···NH3, HCOOH···NH3, HCHO···NH2F and HCOOH···NH2F where elongating effects are dominant, the N—H···O hydrogen bonds are red-shifted. 展开更多
关键词 red-shifted H-BOND blue-shifted H-BOND AIM topological analysis nbo analysis
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草酸分子结构与性质的量子化学计算研究 被引量:6
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作者 耿志远 王冬梅 +3 位作者 薄丽丽 戴国梁 吕玲玲 王永成 《西北师范大学学报(自然科学版)》 CAS 2005年第3期58-62,共5页
采用量子化学的MP2,B3LYP,HF计算方法在6311++G水平上,对草酸可能存在的13种构型进行完全放开的全几何优化及振动频率分析,得到8种稳定构型和5种内转动过渡态构型.并对最稳定构型Ⅰ在MP2/6311++G水平上作了NBO和MO分析,讨论了C-C键对草... 采用量子化学的MP2,B3LYP,HF计算方法在6311++G水平上,对草酸可能存在的13种构型进行完全放开的全几何优化及振动频率分析,得到8种稳定构型和5种内转动过渡态构型.并对最稳定构型Ⅰ在MP2/6311++G水平上作了NBO和MO分析,讨论了C-C键对草酸稳定性的影响以及草酸的结构与性质之间的关系. 展开更多
关键词 草酸 从头算 几何构型 MO分析 nbo分析
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DFT and TD-DFT Study of Bis[2-(5-Amino-[1,3,4]-Oxadiazol-2-yl) Phenol](Diaqua)M(II) Complexes [M = Cu, Ni and Zn]: Electronic Structures, Properties and Analyses 被引量:2
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作者 Nyiang Kennet Nkungli Julius Numbonui Ghogomu +1 位作者 Ludovid Ngouo Nogheu Shridhar Ramachandra Gadre 《Computational Chemistry》 2015年第3期29-44,共16页
Ground state geometries, spectral (IR and UV-Vis) properties, analysis of frontier molecular orbitals (FMOs), natural bond orbital (NBO) analysis and molecular electrostatic potential (MEP) surfaces of three transitio... Ground state geometries, spectral (IR and UV-Vis) properties, analysis of frontier molecular orbitals (FMOs), natural bond orbital (NBO) analysis and molecular electrostatic potential (MEP) surfaces of three transition metal complexes [Cu(AOYP)2(OH2)2] (A), [Ni(AOYP)2(OH2)2] (B) and [Zn-(AOYP)2(OH2)2] (C), have been studied theoretically by the Density Functional Theory (DFT) and Time-Dependent Density Functional Theory (TD-DFT) methods. AOYP is the oxadiazole ligand 2-(5-amino-[1,3,4]-oxadiazol-2-yl)phenol. The geometries of these complexes were initially optimized using two basis sets: LAN2DZ and a generic basis set, the latter of which was selected for subsequent analysis. The stability of the complexes arising from intramolecular interactions and electron delocalization was estimated by natural bond orbital (NBO) analysis. The NBO results showed significant charge transfer from lone pair orbitals on the AOYP donor atoms O19, O21, N15 and N36 to central metal ions in the complexes, as well as to the benzene and oxadiazole rings. The electronic spectrum of (A) showed bands at 752 and 550 nm mainly attributable to ligand-to-metal charge transfer (LMCT) transitions, and a band at 446 nm assigned to a d-d transition. The electronic spectrum of (B) consisted of bands at 540, 463 and 395 nm mainly due to d-d transitions. Calculated electronic bands for (C) occurred at 243, 238 and 235 nm, arising from intraligand charge transfer (ILCT) transitions within AOYP. A good agreement in terms of band positions was found between experimental and calculated absorption spectra of the complexes. 展开更多
关键词 DFT TD-DFT AOYP COMPLEXES nbo analysis MEP Surfaces
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β-二酮二亚胺铝化合物的CO插入反应机理及其成键性质分析 被引量:1
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作者 阎林胤 刘霖 +1 位作者 樊芳 杨作银 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2010年第2期30-33,共4页
采用ONIOM(B3LYP/6-31G(d):AM1)方法,对β-二酮二亚胺Al配合物LAl[η2-(CSiMe3)2](L=HC[(CMe)(NAr)]2,Ar=2,6-iPr2C6H3)和LAl[η2-(CPh)2](L=HC[(CMe)(NAr)]2,Ar=2,6-iPr2C6H3)的CO插入反应进行了理论研究,并在B3LYP/6-311G(d,p)水平上... 采用ONIOM(B3LYP/6-31G(d):AM1)方法,对β-二酮二亚胺Al配合物LAl[η2-(CSiMe3)2](L=HC[(CMe)(NAr)]2,Ar=2,6-iPr2C6H3)和LAl[η2-(CPh)2](L=HC[(CMe)(NAr)]2,Ar=2,6-iPr2C6H3)的CO插入反应进行了理论研究,并在B3LYP/6-311G(d,p)水平上分析了反应物、过渡态和产物的键合特征。结果表明:反应活化能和前线分子轨道能级差较低,该插入过程易于进行;与过渡金属原子的酰基配合物不同,主族元素Al的酰基配合物中,Al原子与酰基碳原子之间不存在σ-π配键,而是Al的3s轨道与酰基C原子的sp2杂化轨道形成的电价配键,且Al的酰基配合物可能较过渡金属类似物有更高的化学活性。 展开更多
关键词 铝配合物 酰基化反应 量子化学计算 反应机理 nbo分析
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DFT Calculations and NBO Analysis of 2-Chloroethylethyldichlorosilane Unimolecular Elimination Kinetics in the Gas Phase 被引量:1
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作者 Abolfazl Shiroudi Ehsan Zahedi 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第5期625-634,共10页
Ab initio molecular orbital calculations have been used to investigate the thermal decomposition kinetics of 2-chloroethylethyldichlorosilane at the B3LYP/6-311+G^**,B3PW91/6-311+G^**,and MPW1PW91/6-311+G^** ... Ab initio molecular orbital calculations have been used to investigate the thermal decomposition kinetics of 2-chloroethylethyldichlorosilane at the B3LYP/6-311+G^**,B3PW91/6-311+G^**,and MPW1PW91/6-311+G^** levels of theory.Among these methods,the results(activation parameters) obtained using the B3LYP/6-311+G** level are in good agreement with the available experimental data.The calculated data imply that in the unimolecular β-elimination reactions of the studied compound in the gas phase,the polarization of C(1)-Cl(3) and C(1)-H(4) bonds in the sense of C(1)^δ+-Cl(3)^δ-and C(1)^δ+-H(4)^δ-,respectively,is a determining factor in the gas phase elimination reactions 1,2 and 3.Analysis of bond order,natural bond orbital charges,bond indexes,synchro-nicity parameters,and IRC calculations suggest the elimination of 2-chloroethylethyldichlorosilane via reactions 1~3 can be described as concerted and slightly asynchronous.The transition state structures of these reactions are a four-membered cyclic structure. 展开更多
关键词 theoretical chemistry molecular modeling thermal decomposition DFT nbo analysis IRC 2-chloroethylethyldichlorosilane
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Quantum Mechanical Calculations of High-T<sub>c</sub>Fe-Superconductors 被引量:1
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作者 Ronald Columbié-Leyva Ulises Miranda +2 位作者 Alberto López-Vivas Jacques Soullard Ilya G. Kaplan 《Journal of Quantum Information Science》 2021年第2期84-98,共15页
In introduction we presented a short historical survey of the discovery of superconductivity (SC) up to the Fe-based materials that are not superconducting in a pure state. For this type of material, the transition to... In introduction we presented a short historical survey of the discovery of superconductivity (SC) up to the Fe-based materials that are not superconducting in a pure state. For this type of material, the transition to SC state occurs in presence of different dopants. Recently in the Fe-based materials at high pressures, the SC was obtained at room critical temperature. In this paper, we present the results of calculations of the isolated cluster representing infinitum crystal with Rh and Pd as dopants. All calculations are performed with the suite of programs Gaussian 16. The obtained results are compared with our previous results obtained for embedded cluster using Gaussian 09. In the case of embedded cluster our methodology of the Embedded Cluster Method at the MP2 electron correlation level was applied. In the NBO population analysis two main features are revealed: the independence of charge density transfer from the spin density transfer and, the presence of orbitals with electron density but without spin density. This is similar to the Anderson’s spinless holon and confirms our conclusions in previous publications that the possible mechanism for superconductivity can be the RVB mechanism proposed by Anderson for high T<sub>c</sub> superconductivity in cuprates. 展开更多
关键词 SUPERCONDUCTIVITY Fe-Based Superconductors Embedded Cluster Method MP2 Method nbo analysis
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Synthesis, Crystal Structure and Theoretical Calculations of N-Benzyl-1-(5-(3-chlorophenyl)-1,3,4-oxadiazol-2-yl)cyclopentanamine 被引量:1
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作者 ALI Ramazania FATEMEH Zeinali Nasrabadi +5 位作者 YOUNES Hanifehpour SANG WOO Jooc MASOOME Sheikhi KATARZYNA Slepokura TADEUSZ Lis FARIDEH Gouranlou 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第5期679-692,共14页
N-benzyl-1-(5-(3-chlorophenyl)-1,3,4-oxadiazol-2-yl)cyclopentanamine was synthesized via one-pot reaction of appropriate benzylamine, cyclopentanone,(N-isocyanimino)triphenylphosphorane and m-chlorobenzoic acid.... N-benzyl-1-(5-(3-chlorophenyl)-1,3,4-oxadiazol-2-yl)cyclopentanamine was synthesized via one-pot reaction of appropriate benzylamine, cyclopentanone,(N-isocyanimino)triphenylphosphorane and m-chlorobenzoic acid. The quantum theoretical calculations for crystal structure were performed by density functional theory(DFT/B3LYP/6-311+G*). From the optimized structure, geometric parameters were obtained and experimental measurements were compared with the calculated data. Frontier molecular orbitals(FMOs), total density of states(DOS), molecular electrostatic potential(MEP), molecular properties, natural charges, NMR parameters and NBO analysis for the product were investigated by theoretical calculations. 展开更多
关键词 N-isocyaniminotriphenylphosphorane CYCLOPENTANONE m-chlorobenzoic acid 1 3 4-oxadiazole aza-Wittig reaction DFT nbo analysis
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Quantum Chemical and Corrosion Inhibition Studies of (4-Chlorophenyl)-N-(4-Methylphenyl) Nitrone
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作者 Rubarani.P.Gangadharan S.Sampath Krishnan M.Thirumalaikumar 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2019年第12期3940-3945,共6页
The compound(4-chlorophenyl)-N-(4-methylphenyl)nitrone(4CPNMPN)has been selected as one of the new nitrone derivative for our study.The molecular structure of the compound was investigated based on frontier orbital an... The compound(4-chlorophenyl)-N-(4-methylphenyl)nitrone(4CPNMPN)has been selected as one of the new nitrone derivative for our study.The molecular structure of the compound was investigated based on frontier orbital analysis and natural bond orbital(NBO)theory.The present work also focuses on the inhibition efficiency of the compound.It is an attempt to find the correlation between the molecular structure of the compound and possible behaviour like corrosion inhibitors.The NBO analysis and the values of electric dipole moment(μ)of the investigated molecule were computed using DFT calculations.The molecule orbital contributions were studied by using the total(TDOS)density of states.The strong evidences that the compound can be used as an efficient nonlinear optical(NLO)of 4CPNMPN were demonstrated by considerable polarizability and hyperpolarizability values obtained at DFT levels. 展开更多
关键词 MOLECULAR ORBITAL analysis Corrosion INHIBITION nbo analysis
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Pu(H_2O)_5^(3+)和Pu(H_2O)_5^(4+)团簇的相对论密度泛函研究 被引量:1
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作者 冯莎莎 蒋刚 杜际广 《西南民族大学学报(自然科学版)》 CAS 2014年第3期406-409,共4页
用TPSSTPSS密度泛函方法,Pu离子和H2O分子分别采用相对论有效原子实势(RECP)和6-31g基组,研究了Pu(H2O)53+和Pu(H2O)54+团簇溶剂化和非溶剂化效应中的几何结构及紫外可见吸收光谱.计算结果表明:水溶剂环境对Pu(H2O)53+及Pu(H2O)54+团簇... 用TPSSTPSS密度泛函方法,Pu离子和H2O分子分别采用相对论有效原子实势(RECP)和6-31g基组,研究了Pu(H2O)53+和Pu(H2O)54+团簇溶剂化和非溶剂化效应中的几何结构及紫外可见吸收光谱.计算结果表明:水溶剂环境对Pu(H2O)53+及Pu(H2O)54+团簇的几何结构影响都比较明显.NBO电荷分析表明水分子与钚离子之间没有直接的电荷转移.所研究团簇的未配对电子都占据5f轨道.在气相及水溶剂环境下,所研究团簇的紫外可见吸收光谱存在较大差距.主要的吸收峰大都源于f电子之间的跃迁. 展开更多
关键词 Pu(H2O)5^3+和Pu(H2O)5^4+团簇 几何结构 nbo分析 紫外可见吸收光谱
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Visible photoluminescence of polyoxoniobates in aqueous solution and their high electrocatalytic activities for water oxidation
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作者 Yichen Ye Congcong Chen +6 位作者 Hui Feng Jin Zhou Juanjuan Ma Jianrong Chen Junhua Yuan Lichun Kong Zhaosheng Qian 《Open Journal of Inorganic Chemistry》 2013年第3期59-69,共11页
The photoluminescence of four polyoxoniobates [Nb6O19]8-, [Nb10O28]6-, [Ti2Nb8O28]8- and [H2Si4Nb16O56]14- was observed, and its origin was revealed in the view of molecular orbital by means of the computational metho... The photoluminescence of four polyoxoniobates [Nb6O19]8-, [Nb10O28]6-, [Ti2Nb8O28]8- and [H2Si4Nb16O56]14- was observed, and its origin was revealed in the view of molecular orbital by means of the computational method. The photoluminescence is originated from singlet transitions, and the calculated values agree well with the experimental data. The results indicate that the size of clusters and the foreigner atoms can affect the fluorescent properties of PONbs. The absorption and emission of these PONbs are originated molecular orbitals contributed mainly by μ2-O and Nb atoms according to NBO analysis. These PONbs were also found as electrochemical catalysts with high performance for water oxidation, which can effectively split water into oxygen under basic condition with a high catalytic current, and pH values have remarkable influence on the electrocatalytic activities of these PONbs for water oxidation. 展开更多
关键词 PONbs PHOTOLUMINESCENCE nbo analysis ELECTROCATALYSIS Water OXIDATION
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Density functional study of Al-doped Au clusters
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作者 赵丽霞 冯晓娟 +2 位作者 曹廷廷 梁晓 罗有华 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第7期2709-2718,共10页
The equilibrium geometries and electronic properties of AunAl, up to n=13, have been systematically investigated using the density functional theory. The results show that, for the AunAl clusters, two patterns are ide... The equilibrium geometries and electronic properties of AunAl, up to n=13, have been systematically investigated using the density functional theory. The results show that, for the AunAl clusters, two patterns are identified. Pattern one (n=2, 3, 8), the lowest-energy geometries prefer two-dimensional structures. Pattern two (n=4-7, 9-13), the lowest-energy geometries prefer three-dimensional structures. According to the analysis of the binding energy and the fragmentation energy, AunAl clusters with odd n are found to be more stable than those with even n. The same trend of alternation can be illuminated according to the computational results in the HOMO-LUMO gap, the ionization potential, and the electron affinities. The Al atom not only changes the structures of pure gold clusters, but also enhances their stabilities. NBO analysis indicates 6s orbital of Au atom hybridizes with 3p orbital of Al atom. 展开更多
关键词 AunAl clusters equilibrium geometries electronic properties nbo analysis
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Au3催化甲酸分解反应机理的密度泛函研究
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作者 刘雪云 刘子忠 刘红霞 《功能材料》 EI CAS CSCD 北大核心 2017年第8期142-150,共9页
采用密度泛函理论对trans-HCOOH在有无催化剂条件下的各反应通道进行了研究,在B3LYP/6-311+G(d,p)水平上优化了反应通道上各驻点的几何构型,并计算其振动频率和零点能,通过零点能校正计算了各反应通道的活化能。结果表明,trans-HCOOH分... 采用密度泛函理论对trans-HCOOH在有无催化剂条件下的各反应通道进行了研究,在B3LYP/6-311+G(d,p)水平上优化了反应通道上各驻点的几何构型,并计算其振动频率和零点能,通过零点能校正计算了各反应通道的活化能。结果表明,trans-HCOOH分解存在着脱氢与脱水两种途径。在无催化剂条件下,脱氢及脱水路径最佳反应通道速控步骤活化能分别高达319.0和302.2kJ/mol,分子很稳定,很难分解。在Au3催化下,两条路径最佳反应通道速控步活化能明显降低,分别为43.6和82.5kJ/mol,trans-HCOOH更易按照生成CO2和H2的途径来进行分解,Au3催化剂的加入活化了C—H键及O—H键,使速控步骤的活化能显著降低。 展开更多
关键词 Au3催化剂 甲酸 反应机理 密度泛函理论 nbo分析
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1,3-二磷硅杂丙二烯及其相关分子的量子化学计算研究
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作者 张伏龙 《甘肃联合大学学报(自然科学版)》 2009年第6期60-64,共5页
使用abinitio(HF)和密度泛函法(B3LYP,B3P86),在6-311++G(d,p)和6-311++G(3df,2p)水平,对1,3-二磷硅杂丙二烯及其相关分子进行了优化构型的量子化学计算.计算结果表明,标题物分子Ⅰ-Ⅷ为弯曲几何构型,NBO分析表明,在标题物Ⅰ-Ⅳ中,末端S... 使用abinitio(HF)和密度泛函法(B3LYP,B3P86),在6-311++G(d,p)和6-311++G(3df,2p)水平,对1,3-二磷硅杂丙二烯及其相关分子进行了优化构型的量子化学计算.计算结果表明,标题物分子Ⅰ-Ⅷ为弯曲几何构型,NBO分析表明,在标题物Ⅰ-Ⅳ中,末端Si、P原子有孤对电子,标题物Ⅰ中有较弱的Si←P配键和强的P≡P键,标题物Ⅱ中有Si←-P键和P=P健,标题物Ⅲ中有两个Si=P键,标题物Ⅳ中有P-Si键和Si≡P键. 展开更多
关键词 1 3-二磷硅杂丙二烯 构型优化 弯曲几何 nbo分析
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新化合物C_7N_6H_6碳负离子特性理论研究
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作者 周宏伟 王静 《成都师范学院学报》 2014年第9期1-8,共8页
发现和合成新的碳负离子化合物是当今有机化学研究的前沿。交换已知的三均三嗪分子中的C原子和N原子位置,得到分子式为C7N6H6的一种新化合物。它以C原子为中心,称为碳中心三均三嗪。新化合物分子呈草帽形,顶点为C原子,特点为:(1)中心C... 发现和合成新的碳负离子化合物是当今有机化学研究的前沿。交换已知的三均三嗪分子中的C原子和N原子位置,得到分子式为C7N6H6的一种新化合物。它以C原子为中心,称为碳中心三均三嗪。新化合物分子呈草帽形,顶点为C原子,特点为:(1)中心C原子上聚集较多的负电荷,正电荷分布在草帽边沿,使本为中性的分子,中心C原子显示很强的负离子特性;(2)中心C原子的第一电离能很低,极易失去电子。作为潜在的格氏试剂,在金属化学合成及反应中具有广阔的应用前景。文章应用DFT理论,使用Gaussian09软件包,对该分子进行模拟计算,借助分子结构分析,论述该中性分子具有碳负离子性质起因。 展开更多
关键词 碳负离子 nbo分析 C7N6H6 电离能 杂化轨道
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吡咯赖氨酸结构和性能的理论研究
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作者 何文娣 蒲雪梅 《苏州科技学院学报(自然科学版)》 CAS 2014年第4期31-33,共3页
在B3LYP/6-311++G**计算水平下对吡咯赖氨酸进行了研究,得到了其最稳定构象,与实验研究得到的结构一致。通过研究发现在其分子内存在有一个N…H-N分子内氢键。此外,还对吡咯赖氨酸进行了红外振动数据研究和自然键轨道研究。
关键词 吡咯赖氨酸 结构性能 nbo分析
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PdSin(n=1~5)原子簇结构的理论研究
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作者 官文佳 马琳 +1 位作者 孙仁安 阎杰 《辽宁师范大学学报(自然科学版)》 CAS 北大核心 2006年第1期72-76,共5页
利用密度泛涵理论B3LYP方法,在LanL2DZ水平上对PdSin(n=1~5)原子簇进行理论探讨,分别在多重度为1、3、5情况下,优化计算得到其稳定构型,对其中较稳定且对称性好的原子簇在能量、稳定性、自然键轨道等方面进行了讨论,发现在所讨... 利用密度泛涵理论B3LYP方法,在LanL2DZ水平上对PdSin(n=1~5)原子簇进行理论探讨,分别在多重度为1、3、5情况下,优化计算得到其稳定构型,对其中较稳定且对称性好的原子簇在能量、稳定性、自然键轨道等方面进行了讨论,发现在所讨论的PdSin(n=1~5)原子簇中,n=3即PdSi3原子簇最稳定;NBO分析计算表明.Pd原子的4d电子在成铤过程中起重要的作用. 展开更多
关键词 原子集 密度泛涵理论 nbo分析
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不同类型的取代基对β-二酮二亚胺基铝三元环丙烯与CO插入反应的影响
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作者 王琳 杨作银 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2011年第5期40-45,共6页
使用gen(B3LYP/6-31G(d)∶STO-3G)混合基组的量子化学计算方法,探讨了当H,F和CH3作为取代基时,LAl[η2-C2R2](L=HC[(CMe)(NAr)]2,Ar=2,6-iPr2C6H3)与CO发生插入反应的机理,并结合NBO分析的结果讨论了不同取代基的电子效应对反应势垒的... 使用gen(B3LYP/6-31G(d)∶STO-3G)混合基组的量子化学计算方法,探讨了当H,F和CH3作为取代基时,LAl[η2-C2R2](L=HC[(CMe)(NAr)]2,Ar=2,6-iPr2C6H3)与CO发生插入反应的机理,并结合NBO分析的结果讨论了不同取代基的电子效应对反应势垒的影响。结果表明,F作为取代基时反应的势垒最大,CH3最低,即供电子基团取代有利于反应的活性。 展开更多
关键词 电子效应 羰基化反应 反应势垒 量子化学计算 nbo分析
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4,5-二硝基-2-氯咪唑与5-氨基-4-硝基-2-氯咪唑的合成 被引量:1
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作者 卞成明 田鹏飞 吴晓青 《精细化工中间体》 CAS 2017年第3期47-48,59,共3页
以4-硝基-2-氯咪唑为原料,硝化制得4,5-二硝基-2-氯咪唑,然后与氨水反应得到5-氨基-4-硝基-2-氯咪唑,总收率67.8%,采用质谱、红外光谱等进行了结构表征。利用自然键轨道分析了4,5-二硝基-2-氯咪唑的电荷分布,其计算数值与氨化实验结果... 以4-硝基-2-氯咪唑为原料,硝化制得4,5-二硝基-2-氯咪唑,然后与氨水反应得到5-氨基-4-硝基-2-氯咪唑,总收率67.8%,采用质谱、红外光谱等进行了结构表征。利用自然键轨道分析了4,5-二硝基-2-氯咪唑的电荷分布,其计算数值与氨化实验结果相符。 展开更多
关键词 4 5-二硝基-2-氯咪唑 硝化 氨化 自然键轨道分析
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乙醛二聚体内蓝移型氢键的理论研究
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作者 杨颙 张为俊 《化学学报》 SCIE CAS CSCD 北大核心 2009年第7期599-606,共8页
利用理论方法研究了乙醛二聚体内的氢键.在MP2/6-31+G(d),B3LYP/6-31+G(d),B3LYP/6-311++G(d,p)和B3LYP/6-311++G(3df,2p)水平上,利用常规方法和均衡校正方法对3种稳定的乙醛二聚体进行了几何优化和振动频率计算.计算结果表明:在二聚体A... 利用理论方法研究了乙醛二聚体内的氢键.在MP2/6-31+G(d),B3LYP/6-31+G(d),B3LYP/6-311++G(d,p)和B3LYP/6-311++G(3df,2p)水平上,利用常规方法和均衡校正方法对3种稳定的乙醛二聚体进行了几何优化和振动频率计算.计算结果表明:在二聚体A和C中乙醛中C—H键强烈收缩,存在显著的C—H…O蓝移型氢键.自然键轨道(NBO)分析表明,电子供体轨道和电子受体轨道之间相互作用的稳定化能、分子内电子密度重排、轨道再杂化和结构重组是决定氢键红移和蓝移的主要因素.其中,轨道间稳定化能属于键伸长效应,分子内电子密度重排、轨道再杂化和电子受体内部结构重组属于键收缩效应.在二聚体A和C中,由于键收缩效应处于优势地位导致C—H…O蓝移氢键存在. 展开更多
关键词 红移型氢键 蓝移型氢键 电子密度拓扑分析 自然键轨道分析
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