CCL: Hund rule

 Sent to CCL by: Iain Moal [Iain.Moal-.-cancer.org.uk]
 Pairing of electrons has an energy cost associated with it; the pairing energy.
 The state of maximum multiplicity has the least number of paired electrons and
 is thus lowest in energy.
 Iain Moal
 ________________________________________
 > From: owner-chemistry+iain.moal==cancer.org.uk(0)ccl.net
 [owner-chemistry+iain.moal==cancer.org.uk(0)ccl.net] On Behalf Of bonoit bonoit
 bonoit_10%x%yahoo.fr [owner-chemistry(0)ccl.net]
 Sent: 21 April 2011 16:23
 To: Iain Moal
 Subject: CCL: Hund rule
 Sent to CCL by: "bonoit  bonoit" [bonoit_10 : yahoo.fr]
 Dear CCLers,
 I'm writting to enquire about the Hund rule:
  "The term with the maximum multiplicity lies lowest in energy"
 My question is:
 What is the origin of this phenomenun?
 Sincerely,
 Bonoithttp://www.ccl.net/cgi-bin/ccl/send_ccl_messagehttp-:-//www.ccl.net/chemistry/sub_unsub.shtmlhttp-:-//www.ccl.net/spammers.txtThis
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