CCL: Dipole moment calculation from non-zero charge distribution

 Sent to CCL by: Marc Baaden []
 thank you for the very enlightening comments, suggestions and references.
 >>> "David F. Green" said:
  >> The standard definition of the dipole moment holds regardless of the
  >> charge. [..]
 Hmm, I'd like to ask: what is the standard definition of a molecular dipole ?
 In several textbooks I found definitions along the line of "A dipole is a
 pair of electric charges of equal magnitude but opposite polarity [..]"
 which *implies* that the net charge is zero. This was also IMHO the
 and somewhat intuitive definition.
 I guess the second moment definition as integral over charge times position
 vector would be a better/more general definition. But what makes
 these definitions equivalent or allows to expand from one to the other ?
 (The first definition a priori breaking down for charged species)
 Also there must be a rationale to discard other definitions, eg one could
 dream up a definition of a molecular dipole as sum of all bond dipoles ?
 Are there seminal references on this ?
 Marc Baaden
  Dr. Marc Baaden  - Institut de Biologie Physico-Chimique, Paris      -
  FAX: +33 15841 5026  -  Tel: +33 15841 5176  ou  +33 609 843217