Molecular and electronic structures of bipolaron in poly-para-phenylene in terms of molecular orbital symmetry

Akira Imamura, Yuuichi Orimoto, Yuriko Aoki

Research output: Contribution to journalArticle

14 Citations (Scopus)

Abstract

The molecular structures of the model systems of the polaron and the bipolaren in poly-paraphenylene (PPP) were calculated by an ab initio molecular orbital (MO) method with fairly sophisticated approximations. The calculated models are monocations, dications, monoanions and dianions of biphenyl, para-terphenyl, para-quaterphenyl, para-quinquephenyl and para-hexaphenyl. The calculations show that the longer the PPP oligomer is, the stronger is the tendency to take on a non-planar twisting structure. This was accounted for by the combination of repulsions between proximate ortho-hydrogen atoms with resonance interactions between benzene π MOs. The magnitude of the resonance interactions was assessed by using the symmetry of benzene π MOs as well as an analytical Hückel solution of the π MO for polyene. In addition, negatively charged polarons and bipolarons were found to have a stronger tendency to take on a planar structure than positively charged ones. This result was also explained by comparing the benzene π HOMO with the benzene π LUMO.

Original languageEnglish
Pages (from-to)180-187
Number of pages8
JournalTheoretical Chemistry Accounts
Volume102
Issue number1-6
DOIs
Publication statusPublished - Jan 1 1999

Fingerprint

Molecular orbitals
Benzene
Molecular Structure
Molecular structure
Electronic structure
molecular orbitals
molecular structure
benzene
electronic structure
symmetry
tendencies
ortho hydrogen
Polyenes
Gene Conversion
Polarons
terphenyls
Molecular Models
planar structures
twisting
polarons

All Science Journal Classification (ASJC) codes

  • Physical and Theoretical Chemistry

Cite this

Molecular and electronic structures of bipolaron in poly-para-phenylene in terms of molecular orbital symmetry. / Imamura, Akira; Orimoto, Yuuichi; Aoki, Yuriko.

In: Theoretical Chemistry Accounts, Vol. 102, No. 1-6, 01.01.1999, p. 180-187.

Research output: Contribution to journalArticle

@article{1648e211dd144e708f2a86eca2afcf2c,
title = "Molecular and electronic structures of bipolaron in poly-para-phenylene in terms of molecular orbital symmetry",
abstract = "The molecular structures of the model systems of the polaron and the bipolaren in poly-paraphenylene (PPP) were calculated by an ab initio molecular orbital (MO) method with fairly sophisticated approximations. The calculated models are monocations, dications, monoanions and dianions of biphenyl, para-terphenyl, para-quaterphenyl, para-quinquephenyl and para-hexaphenyl. The calculations show that the longer the PPP oligomer is, the stronger is the tendency to take on a non-planar twisting structure. This was accounted for by the combination of repulsions between proximate ortho-hydrogen atoms with resonance interactions between benzene π MOs. The magnitude of the resonance interactions was assessed by using the symmetry of benzene π MOs as well as an analytical H{\"u}ckel solution of the π MO for polyene. In addition, negatively charged polarons and bipolarons were found to have a stronger tendency to take on a planar structure than positively charged ones. This result was also explained by comparing the benzene π HOMO with the benzene π LUMO.",
author = "Akira Imamura and Yuuichi Orimoto and Yuriko Aoki",
year = "1999",
month = "1",
day = "1",
doi = "10.1007/s002140050489",
language = "English",
volume = "102",
pages = "180--187",
journal = "Theoretical Chemistry Accounts",
issn = "1432-881X",
publisher = "Springer New York",
number = "1-6",

}

TY - JOUR

T1 - Molecular and electronic structures of bipolaron in poly-para-phenylene in terms of molecular orbital symmetry

AU - Imamura, Akira

AU - Orimoto, Yuuichi

AU - Aoki, Yuriko

PY - 1999/1/1

Y1 - 1999/1/1

N2 - The molecular structures of the model systems of the polaron and the bipolaren in poly-paraphenylene (PPP) were calculated by an ab initio molecular orbital (MO) method with fairly sophisticated approximations. The calculated models are monocations, dications, monoanions and dianions of biphenyl, para-terphenyl, para-quaterphenyl, para-quinquephenyl and para-hexaphenyl. The calculations show that the longer the PPP oligomer is, the stronger is the tendency to take on a non-planar twisting structure. This was accounted for by the combination of repulsions between proximate ortho-hydrogen atoms with resonance interactions between benzene π MOs. The magnitude of the resonance interactions was assessed by using the symmetry of benzene π MOs as well as an analytical Hückel solution of the π MO for polyene. In addition, negatively charged polarons and bipolarons were found to have a stronger tendency to take on a planar structure than positively charged ones. This result was also explained by comparing the benzene π HOMO with the benzene π LUMO.

AB - The molecular structures of the model systems of the polaron and the bipolaren in poly-paraphenylene (PPP) were calculated by an ab initio molecular orbital (MO) method with fairly sophisticated approximations. The calculated models are monocations, dications, monoanions and dianions of biphenyl, para-terphenyl, para-quaterphenyl, para-quinquephenyl and para-hexaphenyl. The calculations show that the longer the PPP oligomer is, the stronger is the tendency to take on a non-planar twisting structure. This was accounted for by the combination of repulsions between proximate ortho-hydrogen atoms with resonance interactions between benzene π MOs. The magnitude of the resonance interactions was assessed by using the symmetry of benzene π MOs as well as an analytical Hückel solution of the π MO for polyene. In addition, negatively charged polarons and bipolarons were found to have a stronger tendency to take on a planar structure than positively charged ones. This result was also explained by comparing the benzene π HOMO with the benzene π LUMO.

UR - http://www.scopus.com/inward/record.url?scp=0033452955&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0033452955&partnerID=8YFLogxK

U2 - 10.1007/s002140050489

DO - 10.1007/s002140050489

M3 - Article

AN - SCOPUS:0033452955

VL - 102

SP - 180

EP - 187

JO - Theoretical Chemistry Accounts

JF - Theoretical Chemistry Accounts

SN - 1432-881X

IS - 1-6

ER -