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1.
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Structure of Pro4H+ investigated by infrared photodissociation（IRPD） spectroscopy and theoretical calculations
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Ru-Xia Feng Lei Mu Shu-Mei Yang Xiang-Lei Kong《中国化学快报》,2016年第27卷第4期
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Combining with electrospray ionization（ESI）mass spectrometry,infrared photodissociation（IRPD）spectroscopy is a powerful method to study structures of cluster ions in the gas phase.In this paper,infrared photodissociation spectrum of Pro4H+in the range of 2700–3600 cm 1was obtained experimentally.Both theoretically predicted spectra of the two most stable isomers of Pro4-1 and Pro4-2 obtained at the level of M062X/6-31+G（d,p）are in good consistent with the experimental results.The two isomers have similar structures and close energies.Both of them only consist of zwitterionic units,indicating the strong salt-bridged interactions inside the clusters.And the calculated collision cross section（ccs）of Pro4-1 is found to be very close to the experimental result previously reported.
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2.
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Theoretical Study on the Stable Structures and Aromaticities for Pnictogen Dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- Clusters
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Xing-bao Wang Xian-xing Chi《化学物理学报(中文版)》,2009年第1期
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Through the theoretical calculation of structural optimization, vibrational frequencies and atomization energies with one method of density functional theory （B3LYP） and two post- Hartree-Fock approaches （MP2, CCSD（T））, several stable isomers for new three pnictogen dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- species were determined. For two homoatomic Sb4^2- and Bi4^2- species, there are three stable isomers： square （D4h）, roof-shaped （C2v-1）, and C2v-2 structure with the square isomer being the ground state. For the heteroatomic dian- ionic （SbBi）2^2- species, there are also three stable isomers： rhombus （D2h）, roof-shaped （C1）, and C2v structures with the rhombic isomer being the ground state. The calculated NICS values show that nucleus-independent chemical shifts （NICS） values of roof-shaped isomers for Sb4^2-, Bi4^2-, and （SbBi）2^2- species are all negative, consequently indicating that these roof-shaped isomers possess aromaticities. NICS values for the planar ring isomers are all positive, suggesting that these three planar ring isomers have antiaromatic characters. The aromaticity for the two stable roof-shaped and square isomers are preliminarily explained and discussed with MO analysis.
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3.
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Studies on the Electronic Structures and Spectra of C78（CH2）3 被引次数：1
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TENG Qi-Wena① WU Shia CHEN Si-Congb a 《结构化学》,2007年第26卷第3期
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The structures and spectra of 20 possible isomers of C78(CH2)3 have been studied by using AM1,INDO/CIS and DFT methods. The results show that the most stable isomer is 1,2,3,4,5,6-C78(CH2)3 (A) with annulene structures,where three -CH2 groups are added to the 6/6 bonds located at the same hexagon passed by the shortest axis of C78 (C2v). Compared with that of C78 (C2v),the first absorption in the electronic spectrum of C78(CH2)3 (A) is blue-shifted because of its wider LUMO-HOMO energy gap. While the IR frequencies of the C–C bonds on the carbon cage are red-shifted owing to the formation of annulene structures and the extension of the conjugated system. The chemical shifts of the carbon atoms in 13C NMR spectra are moved upfield upon the addition.
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4.
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DFT Studies on Non-IPR C_(68) and Endohedral Fullerene Sc_3N@C_(68) 被引次数：3
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WANG Dong-Laia② SUN Xiao-Pingb ZHAI Yu-Chuna a 《结构化学》,2007年第26卷第3期
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The structures and spectra of 20 possible isomers of C78(CH2)3 have been studied by using AM1,INDO/CIS and DFT methods. The results show that the most stable isomer is 1,2,3,4,5,6-C78(CH2)3 (A) with annulene structures,where three -CH2 groups are added to the 6/6 bonds located at the same hexagon passed by the shortest axis of C78 (C2v). Compared with that of C78 (C2v),the first absorption in the electronic spectrum of C78(CH2)3 (A) is blue-shifted because of its wider LUMO-HOMO energy gap. While the IR frequencies of the C–C bonds on the carbon cage are red-shifted owing to the formation of annulene structures and the extension of the conjugated system. The chemical shifts of the carbon atoms in 13C NMR spectra are moved upfield upon the addition.
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5.
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Structures and Aromaticity of Planar XY2Z （X = Li,K, Y - P,As and Z = C,Si, Ge） Clusters
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XU Wen-Guo ZHANG Rui-Chun CHANG Hong-Yan《结构化学》,2009年第28卷第9期
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Clusters XY2Z species are theoretically investigated with density functional theory （DFT） method. The results show that for LiP2C, LiAs2Ge and KAs2C species, the C2v isomer is the most stable planar structure, while for other species the Cs isomer is the most stable planar structure at the B3LYP/6-311＋G＊ level. Wiberg Bond Index （WBI） and Nucleus-Independent Chemical Shift （NICS） values indicate the existence of delocalization in stable planar structures. A detailed Molecular Orbital （MO） analysis further reveals that planar isomers of these species have strong aromatic character, which strengthens the structural stability and makes them closely connect with the concept of aromaticity.
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6.
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Structure and stability of neutral and cationic AlnO clusters
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杨鹏 葛建华 姜振益《中国物理》,2007年第16卷第4期
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In this paper various structural possibilities for AlnO neutral and cationic isomers were investigated by using the B3LYP/6-311G（3df） method. Calculations of this paper predicted the existence of a number of previously unknown isomers. The stabilities of the AlnO （n = 2 - 7） clusters with even n are greater than those with odd n, however the stabilities Of cationic ions have the opposite odd-even alternation. The mass spectra observations of Al17O^＋ and Al19O^＋ ions support our theoretical predictions on their stabilities.
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7.
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Growth of C30 and C31 Clusters： Structures, Energetics and Dynamics
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巩秀芳 王音 宁西京《中国物理快报》,2008年第25卷第2期
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We obtain the isomer spectra of C30 and C31 dusters by time-going-backward quasi-dynamics method and perform molecular dynamics simulations of the duster growth from isolated atoms in He buffer gas at 2500 K. The geometrical structures of the isomers of C30 and C31 can be classified into closed cages, open cages, bowls, sheets and other irregular shapes, where closed cages are found to have the lowest potential energies. However, dynamics simulations show that the sheet structures of C30 and C31 are the dominant outcome at the simulation temperature. Compared with relevant experimental results, we propose a different view in interpreting the experimental data and a research procedure to predict isomers that would be formed most probably under specific experimental conditions.
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8.
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DFT Study on the Structural, Electronic, and Spectroscopic Properties of the Highest Epoxygenated Fullerene C36O18
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ZHANG Jing WANG Zhen《结构化学》,2012年第31卷第10期
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Theoretical investigation on the highest epoxygenated fullerene C36O18 formed from the initial C36 fullerene with D6h symmetry has been performed at the B3LYP/6-31G(d) level. Their equilibrium structures, thermal stabilities, electronic structures, vertical ionization potentials, vertical electron affinities, vibrational frequencies and 13C NMR chemical shifts have been studied. The calculation results showed that C36O18 isomers have higher LUMO-HOMO energy gaps than the fullerene C36 and should be more stable. Compared with C36 , it is less possible for C36O18 to accept or donate electrons from reduced VEAs and enhanced VIPs. It has been found that C36O18 isomers are not aromatic at all or antiaromatic on analyzing the NICS values. The present study will encourage further theoretical and experimental analyses of this system in future.
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9.
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Photoabsorption Spectra of （SiO2）n （n ≤ 5） Clusters on the Basis of Time-Dependent Density Functional Theory
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刘丹丹 张红《中国物理快报》,2010年第27卷第9期
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The photoabsorption spectra of （SiO2）n （n = 2-5） clusters [including isomers （D3h, D2d） structures of （SiO2）3 and （C2v, D2h, D4h） structures of （SiO2）4] are calculated by using time-dependent density-function theory. The equilibrium geometries, the binding energy, the gap between the highest occupied and lowest unoccupied molecular orbitals and vertical ionization potential for corresponding structures are computed using several methods with different types of the basis functions. It is found that the polarizability functions are necessary for the basis functions when optimize the structures of silicon oxide clusters. For different geometries of various clusters and the related isomers, their spectra are very different. Meanwhile, the comparison between using local-density generalized-gradient approximations for exchange-correlation potentials shows that both the calculated spectra present the same spectral feature. We suggest that the calculated photoabsorption spectra could be taken as a tool to elucidate the isomers and dusters structure.
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10.
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Theoretical studies on structures and UV-Vis spectra of C_(70)O
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滕启文 吴师 赵学庄 唐敖庆 封继康《中国科学B辑(英文版)》,1997年第1期
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Systematic studies on eight isomers of C70O were performed by means of INDO methods It has been indicated that the O atom is mainly added to the C1-C2 or C3-C3 bond and an epoxide feature with C1 symmetry is formed.Based on the optimized geometries,the UV-Vis spectra were calculated.It has been found that the main peaks of C70O resemble those of C70 and the characteristic absorptions beyond 460 nm are produced,which is m agree ment with the experimental results.Theoretical assignments about the absorptions were carried out and the reason for the red-shift of the absorptions was discussed.C70O is probably composed of four isomers according to the calculated results.
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11.
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Tunneling spectra of underdoped Bi2Sr2Ca1-xYxCu2O8+δ intrinsic Josephson junctions
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袁涛 王新强 任建坤 林德华 田野 任育峰 赵士平《中国物理 B》,2010年第19卷第8期
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<正>Mesa-structured submicron intrinsic Josephson junctions are successfully fabricated and well characterized on underdoped Bi2Sr2Ca1-xYxCu-2O8+δ single crystals with a Tc of 80 K.Tunneling spectra at the temperatures ranging from 4.2 K to 295 K are measured.A pulse technique is used to reduce sample heating for the measurement near pseudogap opening temperature T*280 K.Our experimental results show that the superconducting gap,the peak-dip separation,and the pseudogap opening temperature are all increased as compared with those from near optimally doped samples,which requires further theoretical analysis in the future.
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12.
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二甲基亚砜溶剂中All-trans-astaxanthin的拉曼和红外光谱
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蒋礼林 刘伟龙 杨延强《化学物理学报》,2017年第30卷第5期
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The Raman and infrared spectra of all-trans-astaxanthin (AXT) in dimethyl sulfoxide (DMSO) solvent were investigated experimentally and theoretically. Density functional cal-culations of the Raman spectra predict the splitting of the υ1 band into υ1-1 and υ1-2 compo-nents. The absence of splitting in Raman experimental spectra is ascribed to the competition between the two symmetric C=C stretching vibrations of the backbone chain. The υ1 band is very sensitive to the excitation wavelength: resonance excitation stimulates the higher-frequency υ1-2 mode, and off-resonance excitation corresponds to the lower-frequency υ1-1 mode. Analyses of the intramolecular hydrogen bonding between C=O and O-H in the AXT/DMSO system reveal that the C4=O1...H1-O3 and C4''=O2...H2-O4 bonds are strengthened and weakened, respectively, in the electronically excited state compared with those in the ground state. This result reveals significant variations of the AXT molecular structure in different electronic states.
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13.
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Gluon saturation and net-proton spectra in relativistic nucleus-nucleus collisions
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王宏民 侯召宇 王秀庭 孙献静《中国物理 C》,2011年第35卷第3期
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By means of the AKK08 fragmentation function, the net-proton transverse momentum (pT) spectra in A+A collisions are studied with two phenomenological models based on the Color Glass Condensate formalism. After a χ2 analysis of the experimental data from BRAHMS, the normalization constant C is extracted at RHIC energies of √sNN=62.4 and 200 GeV, and the theoretical results of the net-proton pT spectra at selected rapidities are also given. It is shown that the theoretical results are in good agreement with the experimental data. Finally, assuming the constant C should have an exponent dependence of √sNN, we also predict the theoretical results of net-proton pT spectra at LHC energies of √sNN=2.76, 3.94, and 5.52 TeV.
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14.
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Determination of the Geometric Structure of Core Excited Silane Based on Photoabsorption Spectra Near the Si 2p Edges
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许如清 李家明 等《中国物理快报》,2002年第19卷第8期
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The photoabsorption spectra near the Si 2p edges of SiH4 have been studied based on the multiple-scattering selfconsistent-field method.Our theoretical calculations provide clear assignments of the inner-shell photoabsorption spectra.In comparison with high-resolution experimental spectra,the geometric structure of the Si 2p excited SiH4^** is recommended as C2v symmetry.
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15.
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Syntheses and Structure of Potassium α-and β-Trivanadoenneatungstogermanates
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CHEN Ya-guang QU Lun-yu PENG Jun and YU Ming 《高等学校化学研究》,1993年第1期
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Potassium α-and β-trivanadoenneatungstogermanates were prepared and characterized by means of elemental analysis, IR, 51V and 183W NMR spectra and polarography. The single crystal structure of a-isomer was determined. The final R is 0. 083. The results show that two prepared heteropoly anions have Keggin structure, and a-isomer belongs to A-type and has stronger oxidizing ability than β-isomer.
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16.
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Effect of metal centres and substituents on the structure and optoelectronic properties of diarylethene compounds: A theoretical study
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LIU ShuJuan YANG ChengJiang XU WenJuan HUANG YanQin YE ShangHui ZHAO Qiang LIU XiangMei HUANG Wei《中国科学:化学(英文版)》,2013年第56卷第1期
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Diarylethene derivatives are a class of fascinating photochromic materials because of their open and closed isomers with different absorption spectra and many other characteristics.To reveal the detailed structure and optoelectronic properties as well as the effect of metal centres and substituents on them,a systematic study on a series of diarylethene derivatives and their Re(I),Pt(II),and Ir(III) complexes was performed via theoretical calculation.The optimized geometries,electronic properties,frontier molecular orbitals,ionization potentials,electron affinities,reorganization energies,and absorption spectra for both of their open-and closed-isomers have been calculated and analyzed.Metal-coordination and substituents exhibit great influence on the photophysical,charge-injection and-transporting characteristics.In addition,the binding of F-with the boron atom of dimesitylboryl group through Lewis acid/base interactions also induces great changes of structural,photophysical and electronic properties for these diarylethene derivatives,and consequently the compound with the substituent of dimesitylboryl group can be used as selective near-infrared phosphorescent F-probe.
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17.
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Theoretical Studies on the Molecular Structures and Thermodynamic Properties of Polychlorinated Fluoranthenes
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ZENG Xiao-Lan WANG Hong-Jun WANG Yan WANG Hui-Juan《结构化学》,2012年第31卷第4期
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DFT-B3LYP/6-311G** method has been used to optimize molecular geometric structures of 527 polychlorinated fluoranthene(PCFRT) congeners and calculate their thermo-dynamic properties in the ideal gas state,such as heat capacity at constant volume(Cv),entropy(S),standard enthalpy of formation(ΔfH) and standard Gibbs free energy of formation(ΔfG).The relations of Cv,S,ΔfH and ΔfG with the number and position of chlorine atoms have also been explored,from which the relative stability of PCFRT congeners was theoretically proposed according to the magnitude of the relative standard Gibbs free energy of formation(Δr,fG).It was found that some of the PCFRT isomers are in a nonplanar configuration and there are intramolecular Cl…Cl weak interactions in some of the isomers.With increasing the number of chlorine atoms,the values of ΔfH and ΔfG of the most stable PCFRT isomers decrease initially and then increase.The values of ΔfH and ΔfG of PCFRT congeners with the same number of chlorine atoms show a strong dependence on the positions of chlorine atoms.The relative thermodynamic stability of PCFRT isomers is determined mainly by intramolecular adjacent Cl…Cl nuclear repulsive interaction between Cl atoms at two different six-membered rings.Most PCFRT congeners are easier to form thermodynamically than their parent compound.
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18.
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Transfer characterization of sulfur from coal-burning emission to plant leaves by PIXE and XANES 被引次数：1
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包良满 张桂林 张元勋 李燕 林俊 刘卫 曹清晨 赵屹东 马陈燕 韩勇《中国物理 C》,2009年第33卷第11期
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The impact of coal-burning emission on sulfur in camphor leaves was investigated using Proton Induced X-ray Emission (PIXE) and synchrotron radiation technique X-ray Absorption Near-Edge Structure (XANES) spectroscopy. The PIXE results show that the sulfur concentrations in the leaves collected at the polluted site are significantly higher than those in controls. The Sulfur XANES spectra show the presence of organic (disulfides, thiols, thioethers, sulfonates and sulfoxides) and inorganic sulfur (sulfates) in the leaves. The inorganic sulfur in the leaves of camphor tree polluted by coal combustion is 15% more than that of the control site. The results suggest that the long-term coal-burning pollution resulted in an enhanced content of the total sulfur and sulfate in the leaves, and the uptake of sulfur by leaves had exceeded the metabolic requirement of plants and the excess of sulfur was stored as SO42－. It can monitor the sulfur pollution in atmosphere.
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19.
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Isomers of the Cu5 cluster:a density function theory study
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龚恒风 李公平 贾艳辉《中国物理 B》,2011年第20卷第3期
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In this work,a systematic study of some possible isomer structures of the Cu 5 cluster obtained from density functional theory methods is presented.The polarisation and pseudopotential basis sets are employed in the calculations.The results show that the binding energies,frequencies,coordination numbers and average bond lengths are in reasonable agreement with reported experimental data.Moreover,four isomers of the Cu 5 cluster are obtained according to calculations,in which the most stable configuration is the planar structure.Meanwhile,two three-dimensional structures of the Cu 5 cluster are obtained in this work,which might be valuable for further theoretical and experimental studies.In addition,our study proves the possibility of the isomer structures of the Cu 5 cluster.
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20.
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Semi-Empirical and DFT Studies on Structures and Spectra for C78（CH2）2
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吴师 滕启文 陈思聪《中国化学》,2007年第25卷第2期
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Eighteen possible isomers of C78（CH2）2 weTe investigated by the INDO method. It was indicated that the most stable isomer was 42,43,62,63-C78（CH2）2, where the -CH2 groups were added to the 6/6 bonds located at the same hexagon passed by the longest axis of C78 （C2v）, to form cyclopropane structures. Based on the most stable four geometries of C78（CH2）2 optimized at B3LYP/3-21G level, the first absorptions in the electronic spectra calculated with the INDO/CIS method and the IR frequencies of the C-C bonds on the carbon cage computed using the AM1 method were blue-shifted compared with those of C78 （C2v） because of the bigger LUMO-HOMO energy gap and the less conjugated carbon cage after the addition. The chemical shifts of ^13C NMR for the carbon atoms on the added bonds calculated at B3LYP/3-21G level were moved upfield thanks to the conversion from sp^2-C to sp^3-C.
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