CCL: Help with halogen bonding

From: "Mariya al-Rashida" <maria_al_rashida!^!hotmail.com>
Subject: CCL: Help with halogen bonding
Date: Fri, 14 May 2010 03:28:21 -0400

 Sent to CCL by: "Mariya  al-Rashida" [maria_al_rashida~!~hotmail.com]
 Hello everyone
 Im currently investigating crystal structures of some organic halogen compounds.
 I'm pretty sure i've come across some "Halogen Bonds" [haolgen bonds
 are non covalent interactions C-X...Y where X = halogen acting as lewis acceptor
 and Y = N or O acting lewis base]. What i know from literature, both exp and
 theoretical is that these interactions are found at distances equal to or
 slightly shorter than sum of van der wall radii. Whereas i'm getting these
 interactions at distance which is equal to sum of van der wall radii + 0.1. Does
 this still count as a halogen bond ??? Or should it be rather a weak type of
 haolgen bonding?
 Also does anyone know of any relavent theoretical literature for halogen bonding
 Your comments will be highly apreciated
 Mariiya