Study of hopping transport in long oligothiophenes and oligoselenophenes: Dependence of reorganization energy on chain length

被引:80
作者
Zade, Sanjio S. [1 ]
Bendikov, Michael [1 ]
机构
[1] Weizmann Inst Sci, Dept Organ Chem, IL-76100 Rehovot, Israel
关键词
charge transfer; density functional calculations; oligoselenophenes; oligothiophenes; semiconductors;
D O I
10.1002/chem.200701182
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
Internal reorganization energies for self-exchange hole-transfer process were calculated at the B3LYP/6-31G(d) level of theory for a series of oligothiophenes and oligoselenophenes up to the 50-mers. This is the first study of reorganization energy in very long it-conjugated systems. We observed a linear correlation between reorganization energy and the reciprocal chain length for these long pi-conjugated heterocyclic oligomers, which can be explained by the changes in bond length that occur between the neutral and cation radical species and by the charge distribution in the cation radicals. In contrast to the saturation behavior observed for the HOMO-LUMO gaps of long pi-conjugated heterocyclic oligomers, the reorganization energy does not show saturation behavior for any length of the oligomers in this study, even up to the 50-mers. Interestingly, the reorganization energy approaches zero for infinite numbers of oligomer units (at the B3LYP/6-31G(d) level of theory), that is, for polythiophene and polyselenophene. The absolute values of the reorganization energies of oligoselenophenes, and the changes that occur in those energies with chain length, are similar to those found for oligothiophenes.
引用
收藏
页码:6734 / 6741
页数:8
相关论文
共 91 条
[1]  
[Anonymous], 1998, ELECT MAT OLIGOMER A
[2]  
[Anonymous], HDB OLIGO POLYTHIOPH
[3]   Functionalized pentacene: Improved electronic properties from control of solid-state order [J].
Anthony, JE ;
Brooks, JS ;
Eaton, DL ;
Parkin, SR .
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY, 2001, 123 (38) :9482-9483
[4]   Predictive study of charge transport in disordered semiconducting polymers [J].
Athanasopoulos, Stavros ;
Kirkpatrick, James ;
Martinez, Diego ;
Frost, Jarvist M. ;
Foden, Clare M. ;
Walker, Alison B. ;
Nelson, Jenny .
NANO LETTERS, 2007, 7 (06) :1785-1788
[5]   Attempts to model neutral solitons in polyacetylene by ab initio and density functional methods.: The nature of the spin distribution in polyenyl radicals [J].
Bally, T ;
Hrovat, DA ;
Borden, WT .
PHYSICAL CHEMISTRY CHEMICAL PHYSICS, 2000, 2 (15) :3363-3371
[6]   Soluble and processable regioregular poly(3-hexylthiophene) for thin film field-effect transistor applications with high mobility [J].
Bao, Z ;
Dodabalapur, A ;
Lovinger, AJ .
APPLIED PHYSICS LETTERS, 1996, 69 (26) :4108-4110
[7]   The versatile thiophene: An overview of recent research on thiophene-based materials [J].
Barbarella, G ;
Melucci, M ;
Sotgiu, G .
ADVANCED MATERIALS, 2005, 17 (13) :1581-1593
[8]   Tetrathiafulvalenes, oligoacenenes, and their buckminsterfullerene derivatives: The brick and mortar of organic electronics [J].
Bendikov, M ;
Wudl, F ;
Perepichka, DF .
CHEMICAL REVIEWS, 2004, 104 (11) :4891-4945
[9]  
Brabec CJ, 2001, ADV FUNCT MATER, V11, P15, DOI 10.1002/1616-3028(200102)11:1<15::AID-ADFM15>3.0.CO
[10]  
2-A