IODINE AND HALOGEN BONDING

This chapter presents a brief overview of selected halogen-bonded systems involving exclusively iodine molecule (I2) as halogen bond (XB) donor. It covers only a part of the contributions that I2 has given to supramolecular chemistry during the past few years. The ultraviolet–visible (UV–VIS) spectroscopy provided important information on the strength of I2 molecule as an XB donor. Infrared (IR) spectroscopy is a valuable tool to study halogen-bonded complexes formed by I2. Raman spectroscopy can be considered a very reliable tool for identifying the iodine moiety in neutral I2-D adducts and polyiodide species both in solution and in the solid state. XB is playing an increasingly important role in crystal engineering and solid-state chemistry, and it is not surprising to find several examples where I2 molecules have been used to construct new engineered cocrystals. The chapter presents inventory of the recent I2-D halogen-bonded system.