# Talk:Electric dipole moment

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## §Free vs bound unexplained

In the derivation where D, E, P, are associated with free, total, and (negative) bound, respectively, there is no definition or motivation of these terms, nor any mathematical formulas relying on the distinction from which we might be able to deduce their meaning. The section ends with:

"Satisfaction of the boundary conditions upon φ may be divided arbitrarily between φf and φb because only the sum φ must satisfy these conditions. It follows that P is simply proportional to the electric field due to the charges selected as bound, with boundary conditions that prove convenient.[8][9]"

The statement "it follows that P is simply proportional to the electric field..." can't possibly follow, because we've said nothing about what P is. 84.227.237.121 (talk) 11:08, 29 March 2014 (UTC)

## §Electric vs electrical

Much more commonly referred to as "electric dipole moment". This comes both from my experience and from a google search showing that "electric dipole moment" results outnumber those for "electrical dipole moment" by a factor of 30.--DJIndica 17:05, 6 November 2007 (UTC)

## §Examples

It would be wonderful if somebody place here any examples of dipole moments. For instance, the one of water. Esmu Igors (talk) 17:43, 7 November 2010 (UTC)

## §Lack of Generality

I have not read the article that carefully, but I can see no mention of the permittivity (e) of the medium in which the charges of an electric dipole are immersed, nor a statement that the discussion relates exclusively to vacuum. As far as I can see, all of the maths expressions include e0 where e*e0 should be written.

## §One of the references is hanging out of the right side of the reference section.

Number 35 isn't below number thirty four, but off to the right of number one. — Preceding unsigned comment added by 72.187.99.79 (talk) 17:54, 11 June 2011 (UTC)

## §Notation, notation, notation...

This article has a terrible mix of upright and italic bold letters for vectors - it should be one or the other. Upright is probably more standard so i'll change all italix vectors to upright. Whoever typed those sections really needs to look after what they write - it jut looks unprofessional...

Furthermore - there is, to my dispair, the insane use of fraktur font. I don't care if its in the sources - i'm changing it to mathcal. It is, always has, always will be, the most appauling, disgusting, font ever used in an equation- completley obliterating its apperance and reproductablility of writing down the symbols. It really does look like a scrawn, sprawled up dead spider..... yuck..... An equation should never have to suffer this grotesque appearance, especially for something this useful. -- 13:59, 27 December 2011 (UTC)

## §Error in dipole field

Last equation of paragraph http://en.wikipedia.org/wiki/Electric_dipole_moment#Potential_and_field_of_an_electric_dipole should have R^5 in denominator in the first term. — Preceding unsigned comment added by 78.128.169.12 (talk) 15:15, 28 May 2012 (UTC)

Since we are using $\hat{\mathbf{R}}$, which is unitless, the denominator should have R^3. --Jebrowne (talk) 04:31, 25 September 2012 (UTC)