BITT - Bremen Initiative on Time-dependent Transport: Atomistic approaches towards photo-induced quantum transport dynamics across single molecules

BITT - 不来梅时间依赖性传输倡议：跨单分子光诱导量子传输动力学的原子方法

• 批准号: 25002299
• 负责人: Professor Dr. Thomas Frauenheim
• 金额: --
• 依托单位: Institut Lumière Matière - ILM (UMR 5306)
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/25002299?language=en
• 关键词: BITT; Bremen; Initiative; Time; dependent

We aim to apply and validate existing State-of-the-Art density-functional-based approaches (Plane Wave, Local Orbital and minimal basis DFTB) in handshaking with quantum chemistry methods to perform calculations of molecules within break-junctions and on different metallic (Au, Cu) and semiconducting (Si) substrates in order to classify accurate and experimental relevant binding geometries. The central goal is to identify the lowest energy configurations and to improve the understanding on how different molecules react and bind to various substrates in vacuo and under environmental conditions. Molecular Dynamics simulations will be performed in order to study thermal fluctuations and dynamical properties of the adsorbates. This is particularly important in the context of break-junction and scanning probe experiments which in most cases show pronounced dynamical signatures due to repeated formation of conduction paths that can also be seen in noise signal. Having obtained the detailed atomic geometries, we will apply ab-initio calculations together with the DFTB code for characterising the electronic structure. Accurate quantum chemistry calculations with correlation-corrections will be applied to small systems to test and validate the effective single-particle approaches.Simulations of scanning tunnelling data (STM images and STS-spectra) will be performed within the framework of non-equilibrium Green¿s functions methods, in order to identify surface reconstructions and morphologies of different surfaces/adsorbates in comparison with experiments.We further will continue developing/improving our non-equilibrium Green¿s functions- DFTB techniques including many-body corrections to the electron-electron correlations and apply this for quantitative calculations of characteristic electronic transport signals across single molecules. This include I-V characteristics, IETS-data, noise analysis and power dissipation. In close collaboration with experimental investigations we aim to understand the molecule contact bonding configurations, the dynamical conformational behaviour of the molecules under applied bias and in coupling to the environment (contacts, dissipation, solution) and we aim to predict, how this will be reflected in the transport data and the functional behaviour of the molecular device.

我们的目标是应用和验证现有的最先进的基于密度泛函的方法（平面波、局域轨道和最小基 DFTB）与量子化学方法的握手，以对断裂结内和不同金属上的分子进行计算（Au、Cu）和半导体（Si）基材，以便对准确且实验相关的结合几何形状进行分类，其中心目标是识别最低能量构型，并提高对不同分子如何反应并与各种基材结合的理解。将进行真空和环境条件下的分子动力学模拟，以研究吸附物的热波动和动力学特性，这在断裂连接和扫描探针实验中尤其重要，这些实验在大多数情况下显示出明显的动力学特征。传导路径的重复形成也可以在噪声信号中看到，有了详细的原子几何形状，我们将应用从头计算和 DFTB 代码来表征精确的电子结构。具有相关校正的量子化学计算将应用于小型系统，以测试和验证有效的单粒子方法。扫描隧道数据（STM 图像和 STS 光谱）的模拟将在非平衡 Green 框架内进行s 函数方法，以便与实验相比识别不同表面/吸附物的表面重建和形态。我们进一步将继续开发/改进我们的非平衡绿色¿其功能 - DFTB 技术包括对电子-电子相关性的多体校正，并将其应用于单个分子的特征电子传输信号的定量计算，其中包括 I-V 特性、IETS 数据、噪声分析和功耗。实验研究我们的目标是了解分子接触键合构型、分子在施加偏压下以及与环境（接触、耗散、溶液）耦合的动态构象行为，并且我们的目标是预测，如何这将反映在分子装置的传输数据和功能行为中。