TY - JOUR
T1 - Intermolecular charge transfer between heterocyclic oligomers. Effects of heteroatom and molecular packing on hopping transport in organic semiconductors
AU - Hutchison, Geoffrey R.
AU - Ratner, Mark A.
AU - Marks, Tobin J.
PY - 2005/12/7
Y1 - 2005/12/7
N2 - For electron or hole transfer between neighboring conducting polymer strands or oligomers, the intrinsic charge-transfer rate is dictated by the charge-resonance integral and by the reorganization energy due to geometric relaxation. To explain conduction anisotropy and other solid-state effects, a multivariate, systematic analysis of bandwidth as a function of intermolecular orientations is undertaken for a series of oligoheterocycles, using first-principles methods. While cofacial oligomers show the greatest bandwidths at a given intermolecular C-C contact distance, for a fixed center-to-center intermolecular distance, tilted π-stacking increases π-overlap (particularly for LUMO orbitals) and decreases electrostatic repulsion, yielding optimum tilt angles for packing of ∼40-60° at small intermolecular separations. The calculations also reveal that bandwidths and intrinsic mobilities of holes and electrons in conjugated oligoheterocycles can be quite comparable.
AB - For electron or hole transfer between neighboring conducting polymer strands or oligomers, the intrinsic charge-transfer rate is dictated by the charge-resonance integral and by the reorganization energy due to geometric relaxation. To explain conduction anisotropy and other solid-state effects, a multivariate, systematic analysis of bandwidth as a function of intermolecular orientations is undertaken for a series of oligoheterocycles, using first-principles methods. While cofacial oligomers show the greatest bandwidths at a given intermolecular C-C contact distance, for a fixed center-to-center intermolecular distance, tilted π-stacking increases π-overlap (particularly for LUMO orbitals) and decreases electrostatic repulsion, yielding optimum tilt angles for packing of ∼40-60° at small intermolecular separations. The calculations also reveal that bandwidths and intrinsic mobilities of holes and electrons in conjugated oligoheterocycles can be quite comparable.
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U2 - 10.1021/ja0533996
DO - 10.1021/ja0533996
M3 - Article
C2 - 16316233
AN - SCOPUS:28844434139
VL - 127
SP - 16866
EP - 16881
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 48
ER -