Please use this identifier to cite or link to this item: http://hdl.handle.net/1942/903
Title: Effect of Thermal Motions on the Structure and UV-Visible Electronic Spectra of Stilbene and Model Oligomers of Poly(p-Phenylene Vinylene)
Authors: KWASNIEWSKI, Sergiusz 
FRANCOIS, Jean-Pierre
DELEUZE, Michael 
Issue Date: 2003
Publisher: ACS
Source: J. Phys. Chem. A, 107(26). p. 5168-5180
Abstract: In the present study, we investigate the influence of temperature on the width and location of bands in the UV-visible absorption spectra of oligomer chains of poly(p-phenylene vinylene) (PPV). These spectra have been computed by means of molecular dynamics (MD) simulations along with the classical MM3 force field, in conjunction with (Z)INDO/S-CIS calculations of vertical excitation energies and transition moments. In addition, the MD(MM3) computations enable consistent insights into the average structures of cis- and trans-stilbene, at temperatures ranging from 0 to 500 K. For trans-stilbene and larger PV-n oligomer chains converging to PPV, thermal motions at room temperature in the vacuum result in a constant broadening of bands by 24 nm (0.20 eV) at half the maximum. Compared with the trans-isomer, thermal broadening intensifies to 33 nm (0.44 eV) for cis-stilbene, due to enhanced steric effects. When accounting in addition for the outcome of vibronic broadening, the width of the first absorption band increases at 300 K to 33 nm (0.48 eV) for trans-stilbene and ~46 nm (0.40 eV) for the largest PV-n chains. At last, upon studying a large molecular cluster reproducing the crystalline structure of trans-stilbene, it has been found that, although they strongly impede the rotations of phenyl rings and out-of-plane distortions, packing effects and steric hindrances in the solid phase lead to a limitation of the width of the first absorption band by 6 nm (0.07 eV) only at 300 K.
Document URI: http://hdl.handle.net/1942/903
Link to publication: http://pubs.acs.org/servlet/reprints/DownloadReprint/jp021853b/v4jq
ISSN: 1089-5639
e-ISSN: 1520-5215
DOI: 10.1021/jp021853b
ISI #: 000183811900004
Category: A1
Type: Journal Contribution
Validations: ecoom 2004
Appears in Collections:Research publications

Show full item record

SCOPUSTM   
Citations

24
checked on Sep 3, 2020

WEB OF SCIENCETM
Citations

25
checked on May 21, 2022

Page view(s)

44
checked on May 20, 2022

Google ScholarTM

Check

Altmetric


Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.