Abstract
One of the major challenges in supramolecular chemistry [1] is the characterization of the (super)structural properties of the (supra)molecular species resulting from self-assembly [2,3] processes. Although the stereoelectronic properties of the supramolecular synthons are responsible for determining the geometries of the final self-assembled (super)strucures, in most instances the experimental conditions (e.g., solvent, temperature, pressure, and stoichiometry) play a dominant role. As a result, the prediction of the geometries of supramolecular entities is difficult and, more often than not, impossible even by means of computational methods [4]. Experimental techniques that are able to establish the (super)structural properties of (supra)molecular species unequivocably are much in demand. X-Ray crystallography has played a major role in determining the superstructures of supermolecules and supramolecular arrays, as well as the structures of large and complex molecular assemblies, in the solid state [5]. The characterization of self-assembled monolayers at the air/water interface — and on solid supports — has been achieved employing sophisticated microscopic techniques e.g., Brewster angle microscopy [6], scanning and transmission electron microscopies (SEM and TEM) [7], atomic force microscopy (AFM) [8] and scanning tunneling microscopy (STM) [9]}. The combination of absorption and emission spectroscopies [10], along with electrochemical techniques [11], has permitted the characterization of self-assembled products in solution. Chromatographic methods e.g., high performance liquid chromatography (HPLC) [12] and gel permeation chromatography (GPC) [13]}, often coupled with mass spectrometric techniques e.g., fast atom bombardment and liquid secondary ion mass spectrometries (FABMS and LSIMS) [14], electrospray mass spectrometry (ESMS) [15], and matrix-assisted laser desorption ionization time-of-flight mass spectometry (MALDI-TOF-MS) [16]}, are becoming more and more powerful analytical methods for the characterization of (supra)molecular species.