Negative Differential Resistance of Oligo(Phenylene Ethynylene) Self-Assembled Monolayer Systems: The Electric-Field-Induced Conformational Change Mechanism
نویسندگان
چکیده
We investigate here a possible mechanism for the room temperature negative differential resistance (NDR) in the Au/AN-OPE/RS/Hg self-assembled monolayer (SAM) system, where AN-OPE = 20-amino,50-nitro-oligo(phenylene ethynylene) and RS is a C14 alkyl thiolate. Kiehl and co-workers showed that this molecular system leads toNDRwith hysteresis and sweep-rate-dependent position and amplitude in the NDR peak. To investigate a molecular basis for this interesting behavior, we combine first-principles quantum mechanics (QM) and mesoscale lattice Monte Carlo methods to simulate the switching as a function of voltage and voltage rate, leading to results consistent with experimental observations. This simulation shows how the structural changes at the microscopic level lead to the NDR and sweep-rate-dependent macroscopic I-V curve observed experimentally, suggesting a microscopic model that might aid in designing improved NDR systems.
منابع مشابه
Negative Differential Resistance of Oligo (Phenylene Ethynylene) Self-Assembled Monolayer Systems: The Electric Field Induced Conformational Change Mechanism – Supporting Information
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