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Am 1 Semiempirical Mo Calculations of Torsional Barriers and Structural Reorganization in Radical Ions of Pbo and Pbzt Model Structures

Published online by Cambridge University Press:  01 January 1992

John W. Connolly  and
Douglas S. Dudis
John W. Connolly
Affiliation:
Dept. of Chemistry, University of Missouri-Kansas City, Kansas City, MO 641 10-2499
Douglas S. Dudis
Affiliation:
WL/MLBP, Wright-Patterson AFB, OH 45433-6533.
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Abstract

AM 1 semiempirical calculations on model structures of neutral, anionic and cationic poly(p-phenylenebenzobisthiazole), PBZT, offer an explanation why the PBZT anion has been shown to be an electrical conductor while the PBZT cation is not. To wit, the highest occupied molecular orbital (HOMO) in the PBZT model structure is centered primarily on the sulfur atoms, resulting in concentration of the positive charge on the sulfur atom when the cation is formed. The lowest occupied molecular orbital (LUMO) is far more delocalized and consequently anion formation produces a species which has electronic charge delocalized over the entire model structure. Similar calculations on model structures of neutral, anionic and cationic poly(p-phenyienebenzobisoxazole), PBO, indicate that both frontier orbitals, i. e., the HOMO and the LUMO are delocalized.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 291: Symposium O – Materials Theory and Modeling , 1992 , 591
Copyright
Copyright © Materials Research Society 1993

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References

REFERENCES

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