Search results
Results from the WOW.Com Content Network
In electromagnetism, charge density is the amount of electric charge per unit length, surface area, or volume. Volume charge density (symbolized by the Greek letter ρ) is the quantity of charge per unit volume, measured in the SI system in coulombs per cubic meter (C⋅m −3), at any point in a volume.
Continuous charge distribution. The volume charge density ρ is the amount of charge per unit volume (cube), surface charge density σ is amount per unit surface area (circle) with outward unit normal nĚ‚, d is the dipole moment between two point charges, the volume density of these is the polarization density P.
The carrier density is important for semiconductors, where it is an important quantity for the process of chemical doping. Using band theory , the electron density, n 0 {\displaystyle n_{0}} is number of electrons per unit volume in the conduction band.
COSMO-RS (short for COnductor like Screening MOdel for Real Solvents) [1] [2] [3] is a quantum chemistry based equilibrium thermodynamics method with the purpose of predicting chemical potentials μ in liquids. It processes the screening charge density σ on the surface of molecules to calculate the chemical potential μ of each species in ...
where k f and k b are the reaction rate constants, with units of frequency (1/time) and c o and c r are the surface concentrations (mol/area) of the oxidized and reduced molecules, respectively (written as c o (0,t) and c r (0,t) in the previous section). The net rate of reaction v and net current density j are then: [Note 2]
Siméon Denis Poisson. Poisson's equation is an elliptic partial differential equation of broad utility in theoretical physics.For example, the solution to Poisson's equation is the potential field caused by a given electric charge or mass density distribution; with the potential field known, one can then calculate the corresponding electrostatic or gravitational (force) field.
Mulliken charges arise from the Mulliken population analysis [1] [2] and provide a means of estimating partial atomic charges from calculations carried out by the methods of computational chemistry, particularly those based on the linear combination of atomic orbitals molecular orbital method, and are routinely used as variables in linear regression (QSAR [3]) procedures. [4]
For dielectric materials, upon the application of an external electric field, [1] the positive charges and negative charges in the material will slightly move in opposite directions, resulting in polarization density in the bulk body and bound charge at the surface. In chemistry, there are many different processes which can lead to a surface ...