Premium
A theoretical investigation on the properties of the new poly( N ‐vinylcarbazole)‐3‐methylthiophene (PVK‐3MeT) synthesized graft copolymer
Author(s) -
Chemek Mourad,
Ayachi Sahbi,
Hlel Abdelkader,
Wéry Jany,
Lefrant Serge,
Alimi Kamel
Publication year - 2011
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.34328
Subject(s) - density functional theory , excited state , homo/lumo , materials science , copolymer , singlet state , ab initio , band gap , photoexcitation , time dependent density functional theory , electronic structure , computational chemistry , polymer , atomic physics , chemistry , physics , molecule , optoelectronics , organic chemistry , composite material
In this article, we present quantum chemical calculations, based on density functional theory (DFT), performed to investigate the geometries and the opto‐electronic properties of a new synthesized graft copolymer based on poly( N ‐vinylcarbazole) (PVK) and poly(3‐methylthiophene) (PMeT) named PVK‐3MeT. First, we have theoretically computed and compared the structural, optical, and vibrational parameters of both neutral and doped states. In addition, the excited state was theoretically obtained by the ab initio RCIS/STO‐3G method. To assign the absorption and emission peaks observed experimentally, we computed the energies of the lowest singlet excited state with the time‐dependent density functional theory (TD‐DFT) method. Electronic parameters such as the HOMO‐LUMO band gap, the ionization potential (IP), and electron affinity (EA) are extracted. Calculations show that the PVK‐3MeT copolymer is nonplanar in its ground neutral state. Meanwhile, upon doping or photoexcitation, an enhancement of the planarity is observed, resulting on a decrease of the inter‐ring torsion angle between 3‐methylthiophene units. Such modifications in the geometric parameters induce a dramatic change on the HOMO and LUMO orbitals in the doped or excited states. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.