Ketonic defects in ladder-type poly(p-phenylene)s

被引：54

作者：

Romaner, L

Heimel, G

Wiesenhofer, H

de Freitas, PS

Scherf, U

Brédas, JL

Zojer, E

List, EJW

机构：

[1] Georgia Inst Technol, Sch Chem & Biochem, Atlanta, GA 30332 USA

[2] Graz Univ Technol, Inst Solid State Phys, A-8010 Graz, Austria

[3] Berg Univ Wuppertal, Fachbereich Chem, D-42097 Wuppertal, Germany

[4] Joanneum Res, Inst Nanostructured Mat & Photon, Christian Doppler Lab Adv Funct Mat, A-8160 Weiz, Austria

来源：

CHEMISTRY OF MATERIALS | 2004年 / 16卷 / 23期

关键词：

D O I：

10.1021/cm0496164

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

We investigate the oxidative degradation process occurring in ladder-type poly(p-phenylene) (LPPP) by spectroscopic and quantum-chemical techniques. Annealing experiments carried out for two representatives of the class of LPPP's with different side chains relate the change in emissive behavior of the polymer to the presence of ketonic defects on the main chain. The geometry, excitation, and emission energies as well as vibrational modes are calculated for model LPPP oligomers bearing these defects. The optical properties of these molecules are significantly changed compared to the pristine model systems. In the excited-state geometry, ketone-containing oligomers possess emissive excited states in the energy region of the experimentally observed low-energy emission band. The calculated infrared (IR) absorption peaks associated with the defects can also be correlated with the experimental IR spectra.

引用

页码：4667 / 4674

页数：8

共 34 条

[1] Exchange functionals with improved long-range behavior and adiabatic connection methods without adjustable parameters:: The mPW and mPW1PW models [J].