A Variational Definition of Electrostatic Potential Derived Charges

2004 ◽  
Vol 108 (23) ◽  
pp. 7963-7968 ◽  
Author(s):  
Alessandro Laio ◽  
Francesco Luigi Gervasio ◽  
Joost VandeVondele ◽  
Marialore Sulpizi ◽  
Ursula Rothlisberger
Keyword(s):  
Electrostatic Potential ◽  
Definition Of ◽  
Potential Derived Charges

Preliminaries

1996 ◽  
Author(s):  
Wolfgang Schmickler
Keyword(s):  
Charged Particle ◽  
Surface Science ◽  
Electrostatic Potential ◽  
Point Charge ◽  
Chemical Interaction ◽  
Dipole Moments ◽  
Great Success ◽  
Definition Of ◽  
Electrified Interfaces ◽  
Electrochemical Interfaces

In this chapter we introduce and discuss a number of concepts that are commonly used in the electrochemical literature and in the remainder of this book. In particular we will illuminate the relation of electrochemical concepts to those used in related disciplines. Electrochemistry has much in common with surface science, which is the study of solid surfaces in contact with a gas phase or, more commonly, with ultrahigh vacuum (uhv). A number of surface science techniques has been applied to electrochemical interfaces with great success. Conversely, surface scientists have become attracted to electrochemistry because the electrode charge (or equivalently the potential) is a useful variable which cannot be well controlled for surfaces in uhv. This has led to a laudable attempt to use similar terminologies for these two related sciences, and to introduce the concepts of the absolute scale of electrochemical potentials and the Fermi level of a redox reaction into electrochemistry. Unfortunately, there is some confusion of these terms in the literature, even though they are quite simple. Electrochemical interfaces are sometimes referred to as electrified interfaces, meaning that potential differences, charge densities, dipole moments, and electric currents occur. It is obviously important to have a precise definition of the electrostatic potential of a phase. There are two different concepts. The outer or Volta potential ψα of the phase a is the work required to bring a unit point charge from infinity to a point just outside the surface of the phase. By "just outside" we mean a position very close to the surface, but so far away that the image interaction with the phase can be ignored; in practice, that means a distance of about 10-5 — 10-3 cm from the surface. Obviously, the outer potential ψα is a measurable quantity. In contrast, the inner or Galvani potential ϕα is defined as the work required to bring a unit point charge from infinity to a point inside the phase α; so this is the electrostatic potential which is actually experienced by a charged particle inside the phase. Unfortunately, the inner potential cannot be measured: If one brings a real charged particle - as opposed to a point charge - into the phase, additional work is required due to the chemical interaction of this particle with other particles in the phase. For example, if one brings an electron into a metal, one has to do not only electrostatic work, but also work against the exchange and correlation energies.

scholarly journals van der Waals Potential: An Important Complement to Molecular Electrostatic Potential in Studying Intermolecular Interactions

2020 ◽  
Author(s):  
Tian Lu ◽  
Qinxue Chen
Keyword(s):  
Electrostatic Potential ◽  
Molecular Electrostatic Potential ◽  
Visual Analysis ◽  
Weak Interactions ◽  
Van Der Waals ◽  
Dynamics Simulation ◽  
Practical Implementation ◽  
Spatial Distribution Function ◽  
Definition Of

Electrostatic and van der Waals (vdW) interactions are two major components of intermolecular weak interactions. Electrostatic potential has been a very popular function in revealing electrostatic interaction between the system under study and other species, while the role of vdW potential is less recognized and has long been ignored. In this paper, we explicitly present definition of vdW potential, describe its practical implementation, and demonstrate its important value by visual analysis and comparing it with spatial distribution function obtained via molecular dynamics simulation. We hope this work can arouse researchers' attention to van der Waals potential and promote its application in practical studies of weak interaction. Calculation, visualization and quantitative analysis of the vdW potential have been supported by our freely available code Multiwfn (http://sobereva.com/multiwfn).

scholarly journals Van Der Waals Potential: An Important Complement to Molecular Electrostatic Potential in Studying Intermolecular Interactions

2020 ◽  
Author(s):  
Tian Lu ◽  
Qinxue Chen
Keyword(s):  
Electrostatic Potential ◽  
Molecular Electrostatic Potential ◽  
Visual Analysis ◽  
Weak Interactions ◽  
Van Der Waals ◽  
Dynamics Simulation ◽  
Practical Implementation ◽  
Spatial Distribution Function ◽  
Definition Of

Electrostatic and van der Waals (vdW) interactions are two major components of intermolecular weak interactions. Electrostatic potential has been a very popular function in revealing electrostatic interaction between the system under study and other species, while the role of vdW potential is less recognized and has long been ignored. In this paper, we explicitly present definition of vdW potential, describe its practical implementation, and demonstrate its important value by visual analysis and comparing it with spatial distribution function obtained via molecular dynamics simulation. We hope this work can arouse researchers' attention to van der Waals potential and promote its application in practical studies of weak interaction. Calculation, visualization and quantitative analysis of the vdW potential have been supported by our freely available code Multiwfn (http://sobereva.com/multiwfn).

Sign in / Sign up

Export Citation Format

Share Document