Computation on the Electronic States of Benzen and Halo-Benzene by Taking into Account the Electron Correlation
| Project/Area Number |
61470013
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (B)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
構造化学
|
|---|
| Research Institution | Hokkaido University |
|---|
Principal Investigator |
OHNO Kimio Fac. of Science, Hokkaido Univ., 理学部, 教授 (40000731)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
NORO Takeshi Fac. of Science, Hokkaido Univ., 理学部, 助手 (50125340)
TANAKA Kiyoshi Fac. of Science, Hokkaido Univ., 理学部, 講師 (00000860)
SASAKI Fukashi Fac. fo Science, Hokkaido Univ., 理学部, 助教授 (90000794)
|
|---|
| Project Period (FY) |
1986 – 1987
|
| Project Status |
Completed (Fiscal Year 1987)
|
| Budget Amount *help |
¥3,800,000 (Direct Cost: ¥3,800,000)
Fiscal Year 1987: ¥1,500,000 (Direct Cost: ¥1,500,000)
Fiscal Year 1986: ¥2,300,000 (Direct Cost: ¥2,300,000)
|
|---|
| Keywords | Benzene / Bolazine / GNO / Electron correlation / <pi>-><pi>^* transition / Perfluor effect / π→σ^*遷移 / Perfluor効果 / ハロベンゼン / 励起状態 / 配置間相互作用法 |
|---|
| Research Abstract |
Contracted Gaussian basis sets have been constructed so as to obtain good description of atomic Hartree-Fock solutions. We point out the importance of obtaining a suitable basis set to describe electron correlation and we started to construct such set for the C atom. By the use of the set [5s3pld] thus obtained for C, we carried out computation on the <pi>-><pi>^* excited state of ethylene and obtained a good agreement of the excitation with experiment. The character of the state is described as valence like state which is expected by the observing the pressureeffect of the absorption spectrum.
The electronic structure of benzene and bolazine are investigated by the use of ccmposite natural orbital (CNO) method which has been proposed by this group. By the use of this method in configuration interaction (CI) calculations, we obtained fast convergence in taking into account the electron correlation. It terned out that the <sigma>-<pi> correlation is significant to obtain good agreement of excitation energy for the ionic excited states of benzene. Three lower lying singlet excited states (S_1, S_2, S_3) have been observed in bolazine and they have been thought to be due to <pi>-><pi>^* transitions. The present calculation supports the assignment of <pi>-><pi>^* transition to S_1 and S_3, whereas the result suggests to assign <pi>-><sigma>^* transition to S_2.
Photo-electron spectra of fluorobenzenes are interpreted by the use of the results by accurate CI calculations. It is pointed out that the empirical rule of the perfluor effect is broken.
|
Report
(2 results)
Research Products
(5 results)
