TY - JOUR

T1 - Polaron-pair binding due to interchain coupling in conjugated polymers

AU - Shuai, Z.

AU - Brédas, J. L.

PY - 1995

Y1 - 1995

N2 - By including both interchain hopping and electron-electron interaction within the context of the Takayama-Lin-Liu-Maki continuum model, and using the (nearly) degenerate perturbation method, we have studied characteristics of the interchain polaron-pair state in conjugated polymers, namely, its binding energy and the transition rate from an intrachain polaron exciton to an interchain polaron pair. It is found that the polaron-pair binding energy due to interchain Coulomb correlation is typically smaller than that due to interchain hopping. We introduce a small energy difference between intrachain and interchain excitations to distinguish their different lattice relaxations; we are then able to establish a two-level model, which can be solved exactly to obtain the transition probability. When is small enough, the solution is just a first-order degenerate perturbation result, i.e., it is proportional to a t binding term; when is large, then it becomes dependent on a (t)2-binding term. In both cases, the interchain electron-correlation effect always appears in first order and is found not to influence the intrachain to interchain transition.

AB - By including both interchain hopping and electron-electron interaction within the context of the Takayama-Lin-Liu-Maki continuum model, and using the (nearly) degenerate perturbation method, we have studied characteristics of the interchain polaron-pair state in conjugated polymers, namely, its binding energy and the transition rate from an intrachain polaron exciton to an interchain polaron pair. It is found that the polaron-pair binding energy due to interchain Coulomb correlation is typically smaller than that due to interchain hopping. We introduce a small energy difference between intrachain and interchain excitations to distinguish their different lattice relaxations; we are then able to establish a two-level model, which can be solved exactly to obtain the transition probability. When is small enough, the solution is just a first-order degenerate perturbation result, i.e., it is proportional to a t binding term; when is large, then it becomes dependent on a (t)2-binding term. In both cases, the interchain electron-correlation effect always appears in first order and is found not to influence the intrachain to interchain transition.

UR - http://www.scopus.com/inward/record.url?scp=0001265596&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0001265596&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.52.13730

DO - 10.1103/PhysRevB.52.13730

M3 - Article

AN - SCOPUS:0001265596

SN - 0163-1829

VL - 52

SP - 13730

EP - 13733

JO - Physical Review B

JF - Physical Review B

IS - 19

ER -