Out-of-equilibrium catalysis of chemical reactions by electronic tunnel currents

Abstract

We present an escape rate theory for current-induced chemical reactions. We use Keldysh nonequilibrium Green's functions to derive a Langevin equation for the reaction coordinate. Due to the out of equilibrium electronic degrees of freedom, the friction, noise, and effective temperature in the Langevin equation depend locally on the reaction coordinate. As an example, we consider the dissociation of diatomic molecules induced by the electronic current from a scanning tunnelling microscope tip. In the resonant tunnelling regime, the molecular dissociation involves two processes which are intricately interconnected: a modification of the potential energy barrier and heating of the molecule. The decrease of the molecular barrier (i.e. the current induced catalytic reduction of the barrier) accompanied by the appearance of the effective, reaction-coordinate-dependent temperature is an alternative mechanism for current-induced chemical reactions, which is distinctly different from the usual paradigm of pumping vibrational degrees of freedom.

Accepted by JCP. Minor revision according to referees, one new figure

References in corpus (6)

• Resonant Electron Transport in Single-Molecule Junctions: Vibrational Excitation, Rectification, Negative Differential Resistance and Local Cooling
• Scattering theory of current-induced forces in mesoscopic systems
• Current-induced nonequilibrium vibrations in single-molecule devices
• Current-induced atomic dynamics, instabilities, and Raman signals: Quasi-classical Langevin equation approach
• Self-consistent theory of molecular switching
• Scattering theory of adiabatic reaction forces due to out-of-equilibrium quantum environments

Cited by in corpus (16)

• Selectivity in single-molecule reactions by tip-induced redox chemistry
• Waiting time distribution for electron transport in a molecular junction with electron-vibration interaction
• Current-induced atomic motion, structural instabilities, and negative temperatures on molecule-electrode interfaces in electronic junctions
• Current-induced dissociation in molecular junctions beyond the paradigm of vibrational heating: The role of anti-bonding electronic states
• Unraveling current-induced dissociation mechanisms in single-molecule junctions
• Nonequilibrium reaction rate theory: Formulation and implementation within the hierarchical equations of motion approach
• Non-renewal statistics for electron transport in a molecular junction with electron-vibration interaction
• Timescale separation solution of Kadanoff-Baym equations for quantum transport in time-dependent fields
• First-passage time theory of activated rate chemical processes in electronic molecular junctions
• Nonequilibrium Green's function theory for nonadiabatic effects in quantum electron transport
• Non-Adiabatic Effects of Nuclear Motion in Quantum Transport of Electrons: A Self-Consistent Keldysh-Langevin Study
• Current-induced bond rupture in single-molecule junctions: Effects of multiple electronic states and vibrational modes
• Cooling molecular electronic junctions by AC current
• Controlling the conductance of molecular junctions using proton transfer reactions: A theoretical model study
• Current-induced forces in nanosystems: A hierarchical equations of motion approach
• Emergence of negative viscosities and colored noise under current-driven Ehrenfest molecular dynamics