Hammett Parameters with Calculated Values of J Electronic Tuning of Magnetic Exchange in Phenoxy-bridged Dinuclear Transition Metal Complexes Vanessa P. McCaffrey, Department of Chemistry, Albion College, Albion MI 49224 Our research is geared toward understanding the connection between the structures of molecules and their physical properties. In particular, we are interested in the extent to which we can use fundamental concepts from the field of organic chemistry to tailor the magnetic properties of inorganic compounds. Phenoxy-bridged dinuclear transition metal complexes are ideal platforms to study fundamental magnetic exchange interactions. The synthesis of these complexes is straightforward and amenable to variety of structural modifications through substitution on the aryl rings or changing the identity of the linking amine bridge. Hammett Parameters with Calculated Values of J  p+ p- JJ J (cm-1) -Br 0.23 0.15 0.25 -3.4 -Cl 0.11 0.19 0.22 -2.8 -CH3 -0.17 -0.31 -2.9 Ĥ = -2JŜ1Ŝ2