Bond dipole and electron density distribution
(©2007, François G. Amar, All rights reserved)

A diatomic molecule has a dipole moment defined by the equation :

µ=Qr

where r is the bond length and Q is the magnitude of the two partial charges at each end of the bond: Q=Q⁺=|Q^-|. If Q is in coulombs (C) and r in m, then µ is in C-m.

note that 1 D or 1 Debye = 3.34x10^-30 C-m

The picture below shows how the electron distribution is symmetrical for F₂ with equal sharing and no bond dipole and unsymmetrical for HF and LiF.

The red color indicates more negative charge

while the blue indicates more positive charge.

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