Anthony Legon has made major contributions to our understanding of the nature of the hydrogen bond, especially the factors that control its directionality, its strength and the extent of proton transfer from the donor to the acceptor. He achieved this through novel applications of rotational spectroscopy. The culmination of a wide range of systematic investigations was a set of powerful and important generalisations, which provide the basis for the accepted model of this ubiquitous interaction.
Subsequently, he made pioneering studies of the halogen bond, a weak intermolecular linkage of increasing importance in chemistry, biology and materials science. By systematically investigating the way in which a Lewis base molecule (for example, ammonia, water or carbon monoxide) binds weakly to a halogen molecule such as fluorine, chlorine or bromine in the gas phase, he showed that there is a striking parallelism between the properties of hydrogen and halogen bonds, particularly in respect of their directionality and strength. Indeed, he established that the generalisations he enunciated earlier for the hydrogen bond also hold for the halogen bond.
Interest and expertise
Public understanding of science
hydrogen bond, , halogen bond , other noncovalent interactions, rotational spectroscopy.