Theory for nanoscale curvature induced enhanced inactivation kinetics of SARS-CoV-2

Abstract

We develop a novel theory for nanomorphology dependent outer sphere heterogeneous electron transfer (ET) rate constant ( k0) based on energy level alignment approach. k0 is modeled through the activation...

Semi-microscopic Theory for the Current Rectification Phenomenon in Nanogap Molecular Devices

“… a One of the electrode/SAM interfaces is fixed as Au/C 8 , and the other electrode/SAM junction energy is altered with Au/DTC- n , varying SAMs from DTC-1 to DTC-9. We report the variation in interface energetics with different molecular self-assemblies at the Au surface with ϕ E 0 = 5.31 eV, E F = 5.53 eV, l TF = 0.123 nm, and ϵ m = 4.39. , The reported values are estimated for the monolayer coverage (θ = 1) of self-assembled molecules with coverage to N 0 = 4.3 nm –2 corresponding to r d = 0.27 nm. The magnitude of the HOMO energy of the electroactive molecule is taken as 5.2 eV .…”

“…Thus, another important aspect is to model the α accounting for the subtle dependence of intrinsic properties of metal electrodes and the self-assembled molecular dipoles at the electrode surface. In this prospect, a generic theoretical approach is required that can be further used to understand the experimentally observable physical quantities such as the potential of zero charge (PZC), , the HET rate constant, , the transfer coefficient for potential, and the exchange current density to further quantify the observed current–potential experimental response of MJs.…”

Theory for Heterogeneous Electron Transfer Kinetics on Nanocorrugated Atomic Stepped Metal Electrodes

“…Formulation of theory for the OS-HET rate constant on atomically stepped metal surface requires a model for activation free energy. The local curvature dependent standard free energy of activation for nanocorrugated atomic steps is given by , normalΔ G ≠ 0em ̃ ( x , y ) = ϕ a d ( x , y ) .25em δ ≠ 0em ̃ ( x , y ) where ϕ ad ( x , y ) is the modified WF of the solvent monolayer covered curved metal jellium for atomic steps and, δ ≠ 0em ̃ ( x , y ) is the fractional electronic charge exchanged in the formation of transition state between the curved metal jellium and electroactive species.…”

“…The dipolar solvent induced reorganization of fraction of electronic charge at the metal jellium surface depends on the dipolar charge on solvent molecules and its orientation. The scaling relation for solvent induced electronic charge reorganization at the metal jellium surface is estimated as δ̃ ≈ prefix± ( μ μ M ) μ e d where μ and μ M represent the dipole moment of the solvent and metal jellium surface, respectively. The magnitude of the metal jellium dipole moment as a consequence of unit electronic charge spillover up to distance 2 l TF (normal to the nominal plane of metal) is given as μ M = 2 el TF and for molecular dipoles with unit charge separation up to distance d is given by ed , with e as the magnitude of electronic charge and d given by d = 2 r d cos(φ) for nonlinear molecules where r d is the radius of adsorbing dipolar molecule and φ is the angle between projected and bond dipoles.…”

“…Heterogeneous electron transfer (HET) phenomena at the electrode/electrolyte interface play a decisive role in several electrochemical devices, viz. sensors, fuel cells, batteries, solar cells, and so on. − It also has a significant role in biological systems and controls the stability of microbes at various surfaces. − Therefore, HET kinetics at the metal/electrolyte interface accounting for the influence of metal surface atomic-scale nanostructures (kinks, steps, facets) and the frontier molecular orbitals of electroactive species are the important key parameters that need further attention. − The electrode materials with layered structures are trending as a current focus because of their ability to strongly influence the HET kinetics. , Several experimental anomalies highlighted the large difference in the HET rate constant at the edge and basal planes. − Most of the current theoretical understanding of outer-sphere heterogeneous electron transfer (OS-HET) reactions is particularly based on rudimentary and computational treatments using model Hamiltonian approaches. , These approaches describe the HET kinetics in terms of fitting parameters generally obtained from first principle calculations considering the simplified systems which are insufficient to unravel the experimental observations of atomic steps (or defect) and kink density induced anomalies in electron transfer kinetics. , Further, extracting the electrode atomic-level insights with contribution from atomic steps and edges density in these approaches is still a challenging issue. Previous experimental observations have suggested that the basal surface in outer- and inner-sphere HET reactions has rather poor electrode kinetics compared to the edge planes for the various redox species. − However, depending on the nature of the electrode material and electroactive species, certain microscopic and nanoscopic studies contradict this finding and indicate that the basal surface also exhibits high ET activity compared to the edge plane. − …”