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Effects of Conformational Diversity and Structural Dynamics on the Optical Properties of Diazoluminomelanin

Published online by Cambridge University Press:  21 March 2011

Kim F. Ferris ,
Steven M. Risser ,
Katrina B. Wagner-Brown ,
Johnathan L. Kiel  and
Richard A. Albanese
Kim F. Ferris
Affiliation:
Materials Sciences Department, Pacific Northwest National Laboratory, Richland, WA 99352
Steven M. Risser
Affiliation:
Battelle Memorial Institute, Columbus, OH 43201
Katrina B. Wagner-Brown
Affiliation:
Conceptual Mindworks, Inc., San Antonio, TX 78228
Johnathan L. Kiel
Affiliation:
Armstrong Laboratory, Brooks AFB, TX 78235
Richard A. Albanese
Affiliation:
Armstrong Laboratory, Brooks AFB, TX 78235
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Abstract

Diazoluminomelanin (DALM) is a luminescent polymer belonging to the broader class of conjugated polyphenylene materials, which has shown significant optical activity in response to perturbing fields. In this paper we use semiempirical electronic structure calculations and molecular dynamics simulations to investigate the molecular structure and absorption characteristics of model phenolic oligomers. Molecular dynamics simulations show the polymer backbone can be extremely flexible depending upon the ionization state of the phenolic hydroxyl groups. The interring torsion angle is a critical variable as it relates charge localization effects and electronic excitation energies. Comparison with experimental data demonstrates the need for a multistate basis to describe the absorption properties of this system.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 598: Symposium BB – Electrical, Optical, & Magenetic Properties...V , 1999 , BB3.40
Copyright
Copyright © Materials Research Society 1999

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