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1.
The high resolution photoelectron spectrum of gaseous p-terphenyl and the spectral response of its photoemission in solid state were measured. Both spectra - gaseous and solid - were in good agreement when a slight shift was assumed. The first vertical ionization potential in the gas phase was 8.20 eV and the potential obtained from the threshold value of the photoemission of crystalline p-terphenyl was 6.1 eV. The conformations in both phases were also discussed. 相似文献
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Harry J.T. Preston Joyce J. Kaufman Jaime Keller J.Bryan Danese John W.D. Connolly 《Chemical physics letters》1976,37(1):55-59
The multiple-scattering Xα model has been applied to the sequence of boron trihalides BX3 where X = F.C1. Br, and I. Transition state calculations show good agreement with the experimental ionization potentials measured by photoelectron spectra. 相似文献
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He I photoelectron (PE) spectra of four carboxylic acids and five esters are measured. Semiempirical and ab initio quantum chemical calculations are used for the interpretation of the spectra. The complex approach which uses empirically established relationships (the dependence of valence electron ionization energies on proton affinities in the gas phase, on the core level ionization energies, and on the structure) was developed. © 1997 John Wiley & Sons, Inc. 相似文献
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Fine-structure vibronic fluorescence spectra of meso-substituted porphyrins and their interpretation
L. L. Gladkov A. S. Starukhin A. M. Shul'ga I. V. Stanishevskii 《Theoretical and Experimental Chemistry》1991,26(6):623-627
Fine-structure fluorescence spectra have been recorded on selective laser excitation at 4.2 K for meso-tetraethylporphyrin (TEP), meso-tetrapropyl-porphyrin (TPP) and their derivatives with deuteriated NH groups. An interpretation of the spectra obtained is proposed on the basis of calculations of the normal vibrations of the molecules. It was noted that the interaction of the ethyl groups of TEP with the solvent leads to different orientations of these groups to the plane of the macrocycle, which leads to an increase in the number of lines in the frequency range 150–400 cm–1 and to their broadening.Translated from Teoreticheskie i Éksperimental'naya Khimiya, Vol. 26, No. 6, pp. 664–668, November–December, 1990. 相似文献
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V. V. Zverev V. M. Vakar' Z. S. Titova B. M. Musin V. B. Ivanov 《Russian Chemical Bulletin》1990,39(1):65-69
According to the data from photoelectron and UV spectroscopy, the molecules of N,N-dimethylmethane sulfenamide and N,N-diethylpropane-2-sulfenamide have a conformation with orthogonal orientation of nN and nS orbitals, while N,N-dimethylbenzene sulfenamide in the gas phase exists in conformational equilibrium of the planar and skewed conformers.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 77–80, January, 1990.We would like to thank F. G. Nasybullina for conducting the GLC analysis. 相似文献
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Gianola AJ Ichino T Hoenigman RL Kato S Bierbaum VM Lineberger WC 《The journal of physical chemistry. A》2005,109(50):11504-11514
The 351.1 nm photoelectron spectrum of imidazolide anion has been measured. The electron affinity (EA) of the imidazolyl radical is determined to be 2.613 +/- 0.006 eV. Vibrational frequencies of 955 +/- 15 and 1365 +/- 20 cm(-1) are observed in the spectrum of the (2)B1 ground state of the imidazolyl radical. The main features in the spectrum are well-reproduced by Franck-Condon simulation based on the optimized geometries and the normal modes obtained at the B3LYP/6-311++G(d,p) level of density functional theory. The two vibrational frequencies are assigned to totally symmetric modes with C-C and N-C stretching motions. Overtone peaks of an in-plane nontotally symmetric mode are observed in the spectrum and attributed to Fermi resonance. Also observed is the photoelectron spectrum of the anion formed by deprotonation of imidazole at the C5 position. The EA of the corresponding radical, 5-imidazolyl, is 1.992 +/- 0.010 eV. The gas phase acidity of imidazole has been determined using a flowing afterglow-selected ion tube; delta(acid)G298 = 342.6 +/- 0.4 and delta(acid)H298 = 349.7 +/- 0.5 kcal mol(-1). From the EA of imidazolyl radical and gas phase acidity of imidazole, the bond dissociation energy for the N-H bond in imidazole is determined to be 95.1 +/- 0.5 kcal mol(-1). These thermodynamic parameters for imidazole and imidazolyl radical are compared with those for pyrrole and pyrrolyl radical, and the effects of the additional N atom in the five-membered ring are discussed. 相似文献
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V. S. Troitskaya N. D. Konevskaya V. G. Vinokurov V. I. Tyulin 《Chemistry of Heterocyclic Compounds》1974,10(4):471-476
The selection of the fundamental frequencies of pyrazole and the assignment of them to various types of vibrations were made on the basis of a comparison of the IR and Raman spectra of pyrazole and some of its isotopically substituted derivatives in various aggregate states and in the form of complexes with CdCl2. The assignment was confirmed by prior calculation of the frequencies and forms of the vibrations of pyrazole. 相似文献
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Vibrational and electronic absorption spectra of PyHI3, PyHIBr2, PyHICl2, PyHBr3 and PyHBrCl2 are presented and explained in terms of the vibrations and electronic transitions, respectively, of the pyridinium and trihalide ions. Two compounds, PyHI3 and PyHBr3, show charge transfer bands in the absorption spectra of the solids, and the vibrational spectrum of the PyH+ ion in solid PyHBr3 differs from the normal PyH+ spectrum. PyHBr3 as well as PyHI3 contains asymmetric trihalide ions in the solid state, as can be concluded from the Raman and infrared spectra. 相似文献
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V. P. Perevalov V. V. Redchenko G. V. Sheban A. B. Kostitsyn L. I. Baryshnenkova B. I. Stepanov 《Chemistry of Heterocyclic Compounds》1986,22(12):1316-1321
The electronic and photoelectron spectra of isomeric vic-aminonitro-1-methylpyrazoles were interpreted by means of the data from PPP and MNDO quantum-chemical calculations.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1629–1634, December, 1986. 相似文献
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The electronic structure of three aza-boron-dipyridomethene derivatives containing different hydrocarbon groups at the boron atom is studied by ultraviolet photoelectron spectroscopy and calculations at the density functional theory level. According to the experimental and theoretical data, the higher occupied molecular orbitals of anthracene, acridine, and the studied complexes are of the same character. For the three studied compounds, the effect of alkyl and phenyl substituents on the electronic structure is determined. The parameters of the electronic structure of aza-boron-dipyridomethene (phenyl groups at the boron atom) and its β-diketonate analogue are compared. It is shown that in an energy range up to 11 eV the calculated results correlate with the ultraviolet photoelectron spectra. 相似文献
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Theoretical and Experimental Chemistry - 相似文献
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S. V. Eroshchenko L. M. Sinegovskaya O. A. Tarasova S. V. Amosova Yu. L. Frolov B. A. Trofimov 《Russian Chemical Bulletin》1989,38(9):1848-1851
The electronic structure of allenyl vinyl ethers (I) has been studied with the aid of photoelectron and UV spectroscopy, as well as MNDO and CNDO/S quantumchemical calculations. Divinyl ether has been selected as a model system for these molecules. The photoelectron spectra of I are similar to the spectrum of divinyl ether, with the exception of the band at 10.2–10.6 eV. The long-wavelength band in the UV spectra of I has been assigned to a transition localized in the allene group. The short-wavelength band of I corresponds to the * transition observed in divinyl ether.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2011–2014, September, 1989. 相似文献
17.
We have obtained for the first time the photoelectron spectra (PES) of 20 diamagnetic and paramagnetic derivatives of imidazole. On the basis of calculations in the MNDO approximation, analysis of the vibrational structure, and comparisons in a series we have interpreted the bands in the range 7–11 eV. In the nitroxyl radicals of 3-imidazoline the highest occupied molecular orbital is the NO
* orbital, having also a contribution on the C4 atom. On introducing N-oxide groups there is a considerable rearrangement of the electronic structure of the radicals. In the PES of the nitroxyl radicals of 3-imidazoline-3-oxide there is multiplet splitting of the ionization band of the no·MO, amounting to 0.3–0.4 eV. Replacement of the methyl groups on the C2 atom by methoxyl groups leads to an increase in the interactions of the unshared pairs of the O atoms of the nitronium and nitroxyl groups, while the same replacement on the C5 atoms leads to a considerable decrease in this interaction. When the substituent on the N1 atom in derivatives of 3-imidazoline-3-oxide is varied the energy of ionization of the C-NO MO decreases in the series: CH3 < H OH < O < NO.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1769–1777, August, 1990. 相似文献
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Photoelectron spectra and electronic structures of some chlorosulfonyl pseudohalides 总被引:2,自引:0,他引:2
Fengyi L Xiaoqing Z Weigang W Lingpeng M Shijun Z Maofa G Dianxun W 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(1):111-116
The electronic structures of chlorosulfonyl pseudohalide ClSO2X (X = Cl, NCO, N3) are studied by photoelectron spectroscopy (PES) combined with the OVGF calculation at 6-311++G(3df) basis sets. The first ionization potentials for ClSO2NCO and ClSO2N3 are determined to be 12.02 and 11.43 eV, respectively, for the first time, and their features in the PE spectra were assigned based on comparison with related compounds and with high level quantum calculations. Photoelectron spectra of ClSO2NCO and ClSO2N3 suggest that the interactions between chlorine "lone-pair" electrons and two pseudohalogen groups have significant effect on the HOMOs of two compounds, besides the influence of their electronegativity on the first ionization energies. 相似文献
19.
E. V. Korotaev N. N. Peregudova L. N. Mazalov V. V. Sokolov A. V. Kalinkin N. A. Kryuchkova Yu. P. Dikov M. I. Buleev I. Yu. Filatova A. Yu. Pichugin 《Journal of Structural Chemistry》2013,54(1):255-258
2p 3/2,1/2 Photoelectron spectra of single crystalline specimens of chromium-copper disulfides CuCrS2 and CuCr0.85V0.15S2 are studied. It is shown that the spectra of single crystalline specimens substantially differ from the corresponding spectra of chromium-copper disulfides in the powder state. 相似文献
20.
R. Gleiter J. Spanget-Larsen R. Bartetzko H. Neunhoeffer M. Clausen 《Chemical physics letters》1983,97(1):94-97
The He(1α) photoeletron (PE) spectra of 1,2,3-triazabenzene and its five mono-, di-, and tri-methyl derivatives are repored. The PE bands are assigned by comparison with the results of molecular orbital (MO) calculations and empirical correlation procedures. 相似文献