Specific features of UV-vis absorption spectra of cis- and trans-polythiophenes.
UV-vis optical spectra of several polythiophene with number of dimers n=1, 5, 10, 15 for cis- and trans-forms were investigated. The study was done theoretically using semi-empirical AM1 (Austin Model 1) and PM3 (Parametric Method 3) methods with the appropriate molecular geometry optimization. The experimental UV-vis absorption spectra were used for verification of the both semi-empirical theoretical models. With the increasing number of dimers a red shift of the absorption edge was observed. Solvent does not play a crucial role on behavior of the absorption spectrum. A comparison of the both semi-empirical methods with the observed experimental absorption spectra is performed. Role of state dipole moments of the investigated polythiophenes in the behavior of the observed UV-vis spectra is discussed. Particular role of pi-conjugated bonds is demonstrated.
Fuks-Janczarek
I
I
Solid State Department, Institute of Physics, J. Długosz University of Czestochowa, Al. Armii Krajowej 13/15, PL42201 Czestochowa, Poland.
Kityk
I V
IV
Miedziński
R
R
Gondek
E
E
Danel
A
A
Zagorska
M
M
D007536:Isomerism; D015394:Molecular Structure; D011108:Polymers / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013876:Thiophenes / Q000737:chemistry*
D011108:Polymers; D013876:Thiophenes; C066730:polythiophene