A Three-Tiered Hierarchical Computational Framework Bridging Molecular Systems and Junction-Level Charge Transport

Abstract

The Non-Equilibrium Green's Function (NEGF) method combined with ab initio calculations has been widely used to study charge transport in molecular junctions. However, the significant computational demands of high-resolution calculations for all device components pose challenges in simulating junctions with complex molecular structures and understanding the functionality of molecular devices. In this study, we developed a series of approximation methods capable of effectively handling the molecular Hamiltonian, electrode self-energy, and their interfacial coupling at different levels of approximation. These methods, as three-tiered hierarchical levels, enable efficient charge transport computations ranging from individual molecules to complete junction systems, achieving an optimal balance between computational cost and accuracy, and are able to addresses specific research objectives by isolating and analyzing the dominant factors governing charge transport. Integrated into a Question-Driven Hierarchical Computation (QDHC) framework, we show this three-tiered framework significantly enhances the efficiency of analyzing charge transport mechanisms, as validated through a series of benchmark studies on diverse molecular junction systems, demonstrating its capability to accurately and efficiently elucidate charge transport mechanisms in complex molecular devices.

References in corpus (26)

• Density functional method for nonequilibrium electron transport
• QuantumATK: An integrated platform of electronic and atomic-scale modelling tools
• Electron transmission through molecules and molecular interfaces
• Renormalization of Molecular Electronic Levels at Metal-Molecule Interfaces
• Mechanically-Controlled Binary Conductance Switching of a Single-Molecule Junction
• Amine-Gold Linked Single-Molecule Junctions: Experiment and Theory
• Improvements on non-equilibrium and transport Green function techniques: the next-generation transiesta
• GOLLUM: a next-generation simulation tool for electron, thermal and spin transport
• Advances and challenges in single-molecule electron transport
• Self-interaction errors in density functional calculations of electronic transport
• Simultaneous Determination of Conductance and Thermopower of Single Molecule Junctions
• Mechanically Controlled Quantum Interference in Individual π-stacked Dimers
• Electron Transport Through Molecules: Self-consistent and Non-self-consistent Approaches
• Semi-Empirical Model for Nano-Scale Device Simulations
• Applicability of the Wide-Band Limit in DFT-Based Molecular Transport Calculations
• Tilt-angle landscapes and temperature dependence of the conductance in biphenyl-dithiol single-molecule junctions
• Cluster-based density-functional approach to quantum transport through molecular and atomic contacts
• Impact of electrode density of states on transport through pyridine-linked single molecule junctions
• A Single-Level Tunnel Model to Account for Electrical Transport through Single Molecule- and Self-Assembled Monolayer-based Junctions
• Coupled electron and phonon transport in one-dimensional atomic junctions
• A DFT-based Molecular Transport Implementation in ADF/BAND
• On the electrostatic potential profile in biased molecular wires
• Important issues facing model-based approaches to tunneling transport in molecular junctions
• Energy Level Alignment at Hybridized Organic-metal Interfaces: the Role of Many-electron Effects
• Energy-dependent resonance broadening in symmetric and asymmetric molecular junctions from an ab initio non-equilibrium Green's function approach
• Ab initio study of charge transport through single oxygen molecules in atomic aluminum contacts