From owner-chemistry@ccl.net Thu Apr 21 18:10:00 2011 From: "Iain Moal Iain.Moal:+:cancer.org.uk" To: CCL Subject: CCL: Hund rule Message-Id: <-44453-110421134908-30114-45xLHN6UZ23bRGEx6JQIgg .. server.ccl.net> X-Original-From: Iain Moal Content-Language: en-GB Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset="us-ascii" Date: Thu, 21 Apr 2011 18:44:50 +0100 MIME-Version: 1.0 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 communication is from Cancer Research UK. Our website is at www.cancerresearchuk.org. We are a registered charity in England and Wales (1089464) and in Scotland (SC041666) and a company limited by guarantee registered in England and Wales under number 4325234. Our registered address is Angel Building, 407 St John Street, London, EC1V 4AD. Our central telephone number is 020 7242 0200. This communication and any attachments contain information which is confidential and may also be privileged. It is for the exclusive use of the intended recipient(s). If you are not the intended recipient(s) please note that any form of disclosure, distribution, copying or use of this communication or the information in it or in any attachments is strictly prohibited and may be unlawful. If you have received this communication in error, please notify the sender and delete the email and destroy any copies of it. E-mail communications cannot be guaranteed to be secure or error free, as information could be intercepted, corrupted, amended, lost, destroyed, arrive late or incomplete, or contain viruses. We do not accept liability for any such matters or their consequences. Anyone who communicates with us by e-mail is taken to accept the risks in doing so.