Effects of electrolyte gating on single-molecule electronic transport

尽管取得了显著的成果，分子电子学仍然面临着重大的困难，例如，通过栅极的单分子传输的有效控制。最近的输运实验证明了电解质门控的重要实用优势。这一领域的进展需要超越目前使用的现象学Newns-Anderson框架的理论理解，其中氧化还原单元被建模为点状单占能级，溶剂被建模为经典振荡器。在与Wandlowski教授（Bern）研究组的密切合作下，我们将首次建立电解质中绝热输运的微观理论，并将逐步完善以接近真空电子学理论的水平。在第一步，我们将执行量子力学/分子力学计算来微观解释内部和外部弛豫，以及多mo（分子轨道）不相关的氧化还原单元。基本上，这是大多数真空电子学研究的理论水平。氧化还原的电子结构接下来将用从头算的方法进行改进，这将消除DFT-“轨道”的物理模糊性，并准确地解释电子相关性。此外，我们将细化氧化还原弛豫的描述，这对电解质门控很重要。该项目的实现将为电解质分子运输的微观理解提供一个新的理论背景。

In spite of significant results, molecular electronics remains confronted with major difficulties, e. g., the efficient control of the single-molecule transport via a gate electrode. Recent transport experiments demonstrated important practical advantages of the electrolyte gating. Advances in this field require a theoretical understanding beyond the presently used phenomenological Newns-Anderson framework, wherein the redox unit is modeled as a point-like singly occupied energy level, and the solvent as a classical oscillator. In close cooperation with the experimental group of Professor Wandlowski (Bern), we will develop for the first time a microscopic theory of the adiabatic transport in electrolytes, which will be refined in a stepwise fashion to approach the level of vacuum electronics theory. In the first step, we will perform quantum-mechanical/molecular mechanics calculations to microscopically account both for the inner and the outer relaxation, and a multi-MO (molecular orbital) uncorrelated redox unit. Basically, this is the theoretical level of most studies in vacuum electronics. The redox’ electronic structure will be next refined within an ab initio approach, which eliminates the physical ambiguity of the DFT-”orbitals” and accurately accounts for electron correlations. Further, we will refine the description of the intra-redox relaxation, which is important for the electrolyte gating. The realization of this project will generate a novel theoretical context for the microscopical understanding of the molecular transport in electrolytes.