| Citation | Stephens is distinguished for the introduction and development of two major techniques for characterising electronic and stereochemical molecular structure using circularly polarised light, namely, Magnetic Circular Dichroism ( MCD ) and Vibrational Circular Dichroism ( VCD ) Spectroscopies. His early theoretical analysis of MCD spectra inspired its widespread application to transition metal coordination complexes and, most significantly, to the characterisation of active sites of metallo-proteins. More recently, Stephens' theory of VCD and its implementation using ab initio methods, combined with experimental measurements, have provided a reliable new method for determining the absolute configurations of chiral organic molecules, most importantly, chiral pharmaceuticals. |