We use explicit-solvent, molecular dynamics simulations to study the change in polar properties of a solvent-accessible surface for proteins undergoing phosphorylation. We analyze eight different pairs of proteins representing different structural classes in native and phosphorylated states and estimate the polarity of their surface using the molecular hydrophobicity potential approach. Whereas...

This review deals with electrostatic potentials within solid/electrolyte interfaces. The electrostatic potentials of several planes are defined and discussed: the inner surface potential affecting the state of charged surface species due to interactions with potential determining ions (Ψ0), the potential affecting the state of associated counterions (Ψβ), the potential at the onset of diffuse l...

Kelvin probe force microscopy (KPFM) is a powerful characterization technique for imaging local electrochemical and electrostatic potential distributions and has been applied across a broad range of materials and devices. Proper interpretation of the local KPFM data can be complicated, however, by convolution of the true surface potential under the tip with additional contributions due to long ...

An analytical model of the electrostatic force between the tip of a non-contact Atomic Force Microscope (nc-AFM) and the (001) surface of an ionic crystal is reported. The model is able to account for the atomic contrast of the local contact potential difference (CPD) observed while nc-AFM-based Kelvin Probe Force Microscopy (KPFM) experiments. With the goal in mind to put in evidence this shor...

To bind at an enzyme's active site, a ligand must diffuse or be transported to the enzyme's surface, and, if the binding site is buried, the ligand must diffuse through the protein to reach it. Although the driving force for ligand binding is often ascribed to the hydrophobic effect, electrostatic interactions also influence the binding process of both charged and nonpolar ligands. First, elect...

Influence of Aluminum, Gallium, Indium- Doping on the Boron-Nitride Nanotubes (BNNTs) investigated with density functional theory (DFT) and Hartreefock (HF) methods. For this purpose, the chemical shift of difference atomic nucleus was studied using the gauge included atomic orbital (GIAO) approch. In the following, structural parameter values, electrostatic potential, thermodynamic parameters,...

The title compound (2,2'-(piperazine-1,4-diyl)bis(N'-((E)-5-chloro-2-hydroxybenzylidene) acetohydrazide) (5-ClPAH) was synthesized by reacting 1,4-Piperazinediacetic acid, 1,4-dihydrazide and 5 -Chloro-2-hydroxybenzaldehyde. Mass spectrometry, 1H, 13C-NMR, IR results of the were examined. Many information about physical chemical properties 5-ClPAH can be obtained theoretical calculations. Densi...

Modeling systems that are not inherently isotropic, e.g., extended bilayers, using molecular simulation techniques poses a potential problem. Since these methods rely on a finite number of atoms and molecules to describe the system, periodic boundary conditions are implemented to avoid edge effects and capture long-range electrostatic interactions. Systems consisting of a solvated bilayer adsor...

A novel way to investigate perturbations of the electrostatic potential across a sample surface is presented, aiming at application in 2D contact phenomena. The idea is to deposit surface state electrons (SSE) on a thin layer of liquid helium covering the surface of a solid state sample. The density of the SSE adjusts to screen perturbations of the electrostatic potential across the sample. As ...