The Theory Study of the Relation between Atoms Electronegativity and Molecules Electronegativity of Halogen

The energy of fluorine,chlorine,bromine atom and molecule and those cation and anion is computed by MP2/6-31g(d,p)、MP2/6-311g(3df,3pd)、B3LYP/6-311g(3df,3pd).The energy of iodine atom and molecule and those cation and anion is computed by MP2/lanl2dz.The atoms and molecules electronegativity of fluorine,chlorine,bromine,iodine are calculated using the energy computed.The result is that atoms electronegativity and molecules electronegativity of halogen change in the same relationship by diffirent method that means halogen atoms electronegativity can describe molecule made up with the two same atom.