Interaction of Self-Localized Excitations with C₆₀ Weak Dopants in Conducting Polymers

Abstract Weak dopants, like C60, (which have LUMO level within the band gap of conducting polymer (CP)) may provide various types of interactions with self-localized (SL) excitations of CP chain: solitons (S˚, S), polaron/bipolarons (P/BP) or excitonpolarons (Ex), whose electronic levels are also located deeply inside the gap. In the present paper we analyse some types of interactions: 1) “Chemical reaction” type charge transfer (CT) processes between charged (P/BP, S) and neutral (S˚, Ex) excitations with C60 molecules intercallated between chains of CP. We stress the important role of SL states of C60 molecule itself: string type polarons (Pc) and bipolarons BP2- c in ttie stabilisation of this reactions through reorientations of string P− c/BP2- c relatively to CP chains resulting ui suppression of backward CT recombination. 2) The C60 mediated interchain hoping of electrons is considered withitin Holstein-Rashba molecular chain polaron approximation, which allows to find exact analytical solutions for two types of local Paround neutral C60 dopant: symmetric (SP) and assymetric (AP) in which the extension (radius) and energy of P change compared to free P. The spectrum of local phonons around P (so called IRAV) is found as a function of C60 mediated hoping strength γ from which the stability criterions for SP in N=2 and 3 chain case are found. SP states are discussed as intermediates for the interchain hoping of

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