Supported by Hunan Province educational science’sproject （No.[2008]263-148）； the Educational Department ofHengyang Normal University（No. jykt200911）~~；
An investigation of the interaction of sulfonating agent with aromatic rings has been initiated through a computational study of complexation of sulfur anhydride with benzene to determine if this is appropriately included as an example of η~6 cation-π interaction.Several initial structures for three types of π complex of sulfur anhydride with benzene,1（η~6）,2（η~2）,3（η~1）,and the Wheland σ complex 4 were fully optimized,three types of π complex η~6,η~2,η~1 have been obtained at several theoretical levels.The results indicate tha...
