Electrical dipole moment

the electrical dipole moment is in physics a measure for the spatial separation of load. One has in a body, e.g. a molecule, at different places an electrical charge of different sign, i.e. if the emphasis of the negative charges (electrons) and the emphasis of the positiveCharges (atomic nuclei) do not collapse, possess this body an electrical dipole moment. The body is then a dipole.

There is also different dipoles (e.g. magnetic dipoles) possible, which therefore also different dipole moments train.

To the electrical dipole moment p ( a vektorgrösse) applies:

<math> \ vec p=Q \ cdot\ vec l </math>

The more highly the charge Q, the more highly also the dipole moment. Even if the charges continue to move away (from the negative to the positive charge arranged distance l) become the dipole moment more largely.

Despite the conversion to the SI system further the cgs unit becomes Debye as unitthe dipole moment used, designated after the Dutch physicist Peter Debye, the reason for the fact lies in the fact that one would have to deal when using the SI-UNIT coulomb meter with very small numbers:

<math> [p] = 1 \ \ mathrm {Debye} = 3.336 \ cdot 10^ {- 30} \ \ mathrm {coulombs} \ \ mathrm {meter cdot} </math>


of molecules the dipole moment lies usually within the range of 0 12 Debye.

Molecule dipole moment in Debye
HBr 0.74
H 2 S 0.92
PF 3 1.025
HCl 1.03
NH 3 1.46
H 2 O 1.844
HF 1.9
NaCl 8.5
key-fields 8.6
AI Regulation
the dipole moment
one can
determine 9.24
KCl 10.27 KBr


CsCl 10.42 [work on] with the help of the Debye equation by measurement of the dielectric constant. Furthermore measurements of the strong effect give information over the dipole moment of a material.


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