The semiempirical calculations were performed to discuss the effects of different substituents on the optical properties of a series of substituted benzonitriles and their corresponding oligomers. The substituents loc...The semiempirical calculations were performed to discuss the effects of different substituents on the optical properties of a series of substituted benzonitriles and their corresponding oligomers. The substituents located in para, meta and ortho-position of the benzenoid ring involve a large range of delta-pi electron-donor-acceptor capability. Theoretical analysis shows that the optical property is affected by the steric and electronic characteristics of the substituents on the benzenoid ring, moreover, the third-order polarizability regularly varies with the polymerization degrees.展开更多
We report in this paper energy positions of the 2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>F);2D<sup>0</sup>_2s<...We report in this paper energy positions of the 2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>F);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)ns(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D)np(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D<sup>0</sup>)np(<sup>2</sup>F), and 4S<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>5</sup>S<sup>0</sup>)np(<sup>4</sup>P) Rydberg series in the photoionization spectra originating from 2D<sup>0</sup> and 4S<sup>0</sup> metastable states of O<sup>+</sup> ion. Calculations are performed up to n = 20 using the Modified Orbital Atomic Theory (MAOT) [1]. The present results are compared to the experimental data of Aguilar et al. [2] which are the only available values. The accurate data presented in this work may be a useful guideline for future experimental and other theoretical studies.展开更多
Semiempirical molecular orbital calculations on the unimolecular massspectrometric fragmentation of tetrahydroimidazole-substituted methylene β-diketones are carried outby Austin Model 1 method, and the calculated re...Semiempirical molecular orbital calculations on the unimolecular massspectrometric fragmentation of tetrahydroimidazole-substituted methylene β-diketones are carried outby Austin Model 1 method, and the calculated results give a strong support to ourexperimental results reported previously. The optimum of the investigated molecular configurationindicates that the two hydrogen atoms attached to nitrogen atom have different activities dueto their chemical environment; the relative energies of the ions in fragmentation pathway ofionized tetrahydroimidazole-substituted methylene β-diketones provide indirectly an evidencefor both the existence of ion/neutral complex and the stabilities of these ions.展开更多
文摘The semiempirical calculations were performed to discuss the effects of different substituents on the optical properties of a series of substituted benzonitriles and their corresponding oligomers. The substituents located in para, meta and ortho-position of the benzenoid ring involve a large range of delta-pi electron-donor-acceptor capability. Theoretical analysis shows that the optical property is affected by the steric and electronic characteristics of the substituents on the benzenoid ring, moreover, the third-order polarizability regularly varies with the polymerization degrees.
文摘We report in this paper energy positions of the 2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>F);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)nd(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>2</sup>(<sup>1</sup>D)ns(<sup>2</sup>D);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D)np(<sup>2</sup>P);2D<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>3</sup>D<sup>0</sup>)np(<sup>2</sup>F), and 4S<sup>0</sup>_2s<sup>2</sup>2p<sup>3</sup>(<sup>5</sup>S<sup>0</sup>)np(<sup>4</sup>P) Rydberg series in the photoionization spectra originating from 2D<sup>0</sup> and 4S<sup>0</sup> metastable states of O<sup>+</sup> ion. Calculations are performed up to n = 20 using the Modified Orbital Atomic Theory (MAOT) [1]. The present results are compared to the experimental data of Aguilar et al. [2] which are the only available values. The accurate data presented in this work may be a useful guideline for future experimental and other theoretical studies.
文摘Semiempirical molecular orbital calculations on the unimolecular massspectrometric fragmentation of tetrahydroimidazole-substituted methylene β-diketones are carried outby Austin Model 1 method, and the calculated results give a strong support to ourexperimental results reported previously. The optimum of the investigated molecular configurationindicates that the two hydrogen atoms attached to nitrogen atom have different activities dueto their chemical environment; the relative energies of the ions in fragmentation pathway ofionized tetrahydroimidazole-substituted methylene β-diketones provide indirectly an evidencefor both the existence of ion/neutral complex and the stabilities of these ions.
