Do coupling exciton and oscillation of electronhole pair exist in neutral and charged pidimeric quinquethiophenes?
Forskningsoutput: Tidskriftsbidrag › Artikel i vetenskaplig tidskrift
Abstract
Optical physical properties of neutral and charged quinquethiophene monomer, and neutral and cationic pidimeric quinquethiophenes were investigated with density functional theory as well as the two dimensional (2D) site (transition density matrix) and three dimensional (3D) cube (transition density and charge difference density) representations, stimulated by the recent experimental report [T. Sakai , J. Am. Chem. Soc. 127, 8082 (2005)]. Transition density shows the orientation and strength of the transition dipole moment of neutral and charged quinquethiophene monomer, and charge difference density reveals the orientation and result of the charge transfer in neutral and charged quinquethiophene monomer. To study if coupling exciton and oscillation of electronhole pair exist in neutral and cationic pidimeric quinquethiophenes, the coupling constants J (coupling exciton of electronhole pair) and K (coupling oscillation of electronhole pair) were introduced to the exciton coordinate and momentum operators, respectively, and the 2D and 3D analysis methods were further developed by extending our previous theoretical methods [M. T. Sun, J. Chem. Phys. 124, 054903 (2006)]. With the new developed 2D and 3D analysis methods, we investigated the excited state properties of neutral and cationic pidimeric quinquethiophenes, especially on the coupling exciton and oscillation of electronhole pair between monomers. The 2D results show that there is neither coupling exciton (J=0) nor oscillation (K=0) of electronhole pair in neutral pidimeric quinquethiophenes. For some excited states of cationic pidimeric quinquethiophenes, there is no coupling exciton (J=0), but there is coupling oscillation (K not equal 0); while for some excited states, there are both coupling exciton and coupling oscillator simultaneously (J not equal 0 and K not equal 0). The strength of transition dipole moments of pidimeric quinquethiophenes were interpreted with 3D transition density, which reveals the orientations of their two subtransition dipole moments. The 3D charge transition density reveals the orientation and result of intermonomer and/or intramonomer charge transfer. The calculated results reveal that excited state properties of neutral pidimeric quinquethiophene are significantly different from those of the cationic pidimeric quinquethiophenes. (c) 2007 American Institute of Physics.
Detaljer
Författare  

Enheter & grupper  
Forskningsområden  Ämnesklassifikation (UKÄ) – OBLIGATORISK

Originalspråk  engelska 

Artikelnummer  084706 
Tidskrift  Journal of Chemical Physics 
Volym  127 
Utgivningsnummer  8 
Status  Published  2007 
Publikationskategori  Forskning 
Peer review utförd  Ja 