Abstract
The He I photoelectron spectra (PES) of 2- and 4-ethynylpyridine were measured, and the origin of each ionization band was clarified. For instance, 4-ethynylpyridine shows five PES bands at 9.58, 9.9, 10.0, 10.75 and 11.84 eV in the lower energy region, the 9.9 eV and 10.75 eV bands in particular being assigned to the ionizations from the atn orbital of the pyridyl group and the in-plane b2π orbital of the ethynyl group, respectively. Furthermore, with the aid of first order perturbation theory, the 10.59 eV band of 2-ethynylpyridine has been ascribed to the ionization from the a2-like π orbital, and the 10.8 eV band to that from the in-plane b2-like π one. Through the process of the band assignments for the ethynylpyridines, it has been revealed that there is a weak interaction between the n orbital on the ortho-substituted nitrogen atom and the in-plane π orbital localized on the ethynyl group of 2-ethynylpyridine. The photoelectron spectra of 1,4-bis(2-pyridyl)-1,3-butadiyne and 1,4-bis(4-pyridyl)-1,3-butadiyne, whose π-electron systems are regarded electronically as double ones of the corresponding ethynylpyridines, were also measured, and we have succeeded in making band assignments of these compounds on the ground of the correlation energy diagram with the ethynylpyridines.
| Original language | English |
|---|---|
| Pages (from-to) | 267-276 |
| Number of pages | 10 |
| Journal | Journal of Electron Spectroscopy and Related Phenomena |
| Volume | 77 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - 1996 Apr 30 |
Fingerprint
Keywords
- Bis(pyridyl)butadiyne
- Ethynylpyridine
- Non-bonding electron pair
- Photoelectron spectroscopy
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Spectroscopy
- Atomic and Molecular Physics, and Optics
- Surfaces and Interfaces
Cite this
Electronic structure of some pyridylacetylenes studied by he I photoelectron spectroscopy : A weak orbital interaction between the nonbonding electron pair on the nitrogen atom and the in-plane π orbital in the ethynyl group. / Okubo, Jun; Shinozakia, Hiraku; Kubota, Mari; Kobayashi, Tsunetoshi.
In: Journal of Electron Spectroscopy and Related Phenomena, Vol. 77, No. 3, 30.04.1996, p. 267-276.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Electronic structure of some pyridylacetylenes studied by he I photoelectron spectroscopy
T2 - A weak orbital interaction between the nonbonding electron pair on the nitrogen atom and the in-plane π orbital in the ethynyl group
AU - Okubo, Jun
AU - Shinozakia, Hiraku
AU - Kubota, Mari
AU - Kobayashi, Tsunetoshi
PY - 1996/4/30
Y1 - 1996/4/30
N2 - The He I photoelectron spectra (PES) of 2- and 4-ethynylpyridine were measured, and the origin of each ionization band was clarified. For instance, 4-ethynylpyridine shows five PES bands at 9.58, 9.9, 10.0, 10.75 and 11.84 eV in the lower energy region, the 9.9 eV and 10.75 eV bands in particular being assigned to the ionizations from the atn orbital of the pyridyl group and the in-plane b2π orbital of the ethynyl group, respectively. Furthermore, with the aid of first order perturbation theory, the 10.59 eV band of 2-ethynylpyridine has been ascribed to the ionization from the a2-like π orbital, and the 10.8 eV band to that from the in-plane b2-like π one. Through the process of the band assignments for the ethynylpyridines, it has been revealed that there is a weak interaction between the n orbital on the ortho-substituted nitrogen atom and the in-plane π orbital localized on the ethynyl group of 2-ethynylpyridine. The photoelectron spectra of 1,4-bis(2-pyridyl)-1,3-butadiyne and 1,4-bis(4-pyridyl)-1,3-butadiyne, whose π-electron systems are regarded electronically as double ones of the corresponding ethynylpyridines, were also measured, and we have succeeded in making band assignments of these compounds on the ground of the correlation energy diagram with the ethynylpyridines.
AB - The He I photoelectron spectra (PES) of 2- and 4-ethynylpyridine were measured, and the origin of each ionization band was clarified. For instance, 4-ethynylpyridine shows five PES bands at 9.58, 9.9, 10.0, 10.75 and 11.84 eV in the lower energy region, the 9.9 eV and 10.75 eV bands in particular being assigned to the ionizations from the atn orbital of the pyridyl group and the in-plane b2π orbital of the ethynyl group, respectively. Furthermore, with the aid of first order perturbation theory, the 10.59 eV band of 2-ethynylpyridine has been ascribed to the ionization from the a2-like π orbital, and the 10.8 eV band to that from the in-plane b2-like π one. Through the process of the band assignments for the ethynylpyridines, it has been revealed that there is a weak interaction between the n orbital on the ortho-substituted nitrogen atom and the in-plane π orbital localized on the ethynyl group of 2-ethynylpyridine. The photoelectron spectra of 1,4-bis(2-pyridyl)-1,3-butadiyne and 1,4-bis(4-pyridyl)-1,3-butadiyne, whose π-electron systems are regarded electronically as double ones of the corresponding ethynylpyridines, were also measured, and we have succeeded in making band assignments of these compounds on the ground of the correlation energy diagram with the ethynylpyridines.
KW - Bis(pyridyl)butadiyne
KW - Ethynylpyridine
KW - Non-bonding electron pair
KW - Photoelectron spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=0008447686&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0008447686&partnerID=8YFLogxK
U2 - 10.1016/0368-2048(95)02549-9
DO - 10.1016/0368-2048(95)02549-9
M3 - Article
AN - SCOPUS:0008447686
VL - 77
SP - 267
EP - 276
JO - Journal of Electron Spectroscopy and Related Phenomena
JF - Journal of Electron Spectroscopy and Related Phenomena
SN - 0368-2048
IS - 3
ER -