Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect

A comprehensive understanding of physical and chemical processes at biological membranes requires the knowledge of the interfacial electric field which is a key parameter for controlling molecular structures and reaction dynamics. An appropriate approach is based on the vibrational Stark effect (VSE...

Descripción completa

Guardado en:
Detalles Bibliográficos
Publicado: 2017
Materias:
Biological membranes
Electrochemical impedance spectroscopy
Electrodes
Light absorption
Molecular dynamics
Quantum chemistry
Reaction kinetics
Self assembled monolayers
Stark effect
Electrode potentials
Electrostatic modeling
Intensity variations
Local electric field
Molecular dynamics simulations
Potential-dependent
Quantum chemical calculations
Surface enhanced infrared absorption spectroscopy
Electric fields
Acceso en línea:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_19327447_v121_n40_p22274_Staffa
http://hdl.handle.net/20.500.12110/paper_19327447_v121_n40_p22274_Staffa
Aporte de:
Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA) de Universidad de Buenos Aires
id paper:paper_19327447_v121_n40_p22274_Staffa
record_format dspace
spelling paper:paper_19327447_v121_n40_p22274_Staffa2023-06-08T16:31:41Z Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect Biological membranes Electrochemical impedance spectroscopy Electrodes Light absorption Molecular dynamics Quantum chemistry Reaction kinetics Self assembled monolayers Stark effect Electrode potentials Electrostatic modeling Intensity variations Local electric field Molecular dynamics simulations Potential-dependent Quantum chemical calculations Surface enhanced infrared absorption spectroscopy Electric fields A comprehensive understanding of physical and chemical processes at biological membranes requires the knowledge of the interfacial electric field which is a key parameter for controlling molecular structures and reaction dynamics. An appropriate approach is based on the vibrational Stark effect (VSE) that exploits the electric-field dependent perturbation of localized vibrational modes. In this work, 6-mercaptohexanenitrile (C5CN) and 7-mercaptoheptanenitrile (C6CN) were used to form self-assembled monolayers (SAMs) on a nanostructured Au electrode as a simple mimic for biomembranes. The C - N stretching mode was probed by surface enhanced infrared absorption (SEIRA) spectroscopy to determine the frequency and intensity as a function of the electrode potential. The intensity variations were related to potential-dependent changes of the nitrile orientation with respect to the electric field. Supported by electrochemical impedance spectroscopy, molecular dynamics simulations, and quantum chemical calculations the frequency changes were translated into profiles of the interfacial electric field, affording field strengths up to 4 × 108 V/m (C6CN) and 1.3 × 109 V/m (C5CN) between +0.4 and 0.4 V (vs Ag/AgCl). These profiles compare very well with the predictions of a simple electrostatic model developed in this work. This model is shown to be applicable to different types of electrode/SAM systems and allows for a quick estimate of interfacial electric fields. Finally, the implications for electric-field dependent processes at biomembranes are discussed. © 2017 American Chemical Society. 2017 https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_19327447_v121_n40_p22274_Staffa http://hdl.handle.net/20.500.12110/paper_19327447_v121_n40_p22274_Staffa
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Biological membranes
Electrochemical impedance spectroscopy
Electrodes
Light absorption
Molecular dynamics
Quantum chemistry
Reaction kinetics
Self assembled monolayers
Stark effect
Electrode potentials
Electrostatic modeling
Intensity variations
Local electric field
Molecular dynamics simulations
Potential-dependent
Quantum chemical calculations
Surface enhanced infrared absorption spectroscopy
Electric fields
spellingShingle Biological membranes
Electrochemical impedance spectroscopy
Electrodes
Light absorption
Molecular dynamics
Quantum chemistry
Reaction kinetics
Self assembled monolayers
Stark effect
Electrode potentials
Electrostatic modeling
Intensity variations
Local electric field
Molecular dynamics simulations
Potential-dependent
Quantum chemical calculations
Surface enhanced infrared absorption spectroscopy
Electric fields
Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect
topic_facet Biological membranes
Electrochemical impedance spectroscopy
Electrodes
Light absorption
Molecular dynamics
Quantum chemistry
Reaction kinetics
Self assembled monolayers
Stark effect
Electrode potentials
Electrostatic modeling
Intensity variations
Local electric field
Molecular dynamics simulations
Potential-dependent
Quantum chemical calculations
Surface enhanced infrared absorption spectroscopy
Electric fields
description A comprehensive understanding of physical and chemical processes at biological membranes requires the knowledge of the interfacial electric field which is a key parameter for controlling molecular structures and reaction dynamics. An appropriate approach is based on the vibrational Stark effect (VSE) that exploits the electric-field dependent perturbation of localized vibrational modes. In this work, 6-mercaptohexanenitrile (C5CN) and 7-mercaptoheptanenitrile (C6CN) were used to form self-assembled monolayers (SAMs) on a nanostructured Au electrode as a simple mimic for biomembranes. The C - N stretching mode was probed by surface enhanced infrared absorption (SEIRA) spectroscopy to determine the frequency and intensity as a function of the electrode potential. The intensity variations were related to potential-dependent changes of the nitrile orientation with respect to the electric field. Supported by electrochemical impedance spectroscopy, molecular dynamics simulations, and quantum chemical calculations the frequency changes were translated into profiles of the interfacial electric field, affording field strengths up to 4 × 108 V/m (C6CN) and 1.3 × 109 V/m (C5CN) between +0.4 and 0.4 V (vs Ag/AgCl). These profiles compare very well with the predictions of a simple electrostatic model developed in this work. This model is shown to be applicable to different types of electrode/SAM systems and allows for a quick estimate of interfacial electric fields. Finally, the implications for electric-field dependent processes at biomembranes are discussed. © 2017 American Chemical Society.
title Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect
title_short Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect
title_full Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect
title_fullStr Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect
title_full_unstemmed Determination of the Local Electric Field at Au/SAM Interfaces Using the Vibrational Stark Effect
title_sort determination of the local electric field at au/sam interfaces using the vibrational stark effect
publishDate 2017
url https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_19327447_v121_n40_p22274_Staffa
http://hdl.handle.net/20.500.12110/paper_19327447_v121_n40_p22274_Staffa
_version_ 1768544201434202112

Ejemplares similares