Abstract
'The exact structures of large, biologically interesting molecules such as proteins are very important for the functions these molecules fulfill. In order to increase our understanding of the relationship between structure and function and to enhance the predictive power of theoretical models the structures of several small model systems have been determined very accurately. Each of these systems is closely related to important structural elements in proteins or DNA. The structure determination itself proceeds through irradiation of these molecules with UV laserlight and subsequent determination of the wavelengths which have been absorbed. From this analysis the rotational energy levels of the molecule can be determined, which are connected to its structure. It turns out that, above all, the structures of systems with multiple chemically weak bonds such as hydrogen bonds differ substantially from theoretical predictions. Since the overall shape of practically all larger biomolecules is determined by these types of bonds, this result has potentially large implications for the analysis of structure and function of biomolecules. The thesis features a comprehensive introduction to the field of high-resolution molecular spectroscopy, assuming a BSc. degree in physics, chemistry or related field. The six following chapters each describe a separate molecular system. These are the benzoic acid dimer (chapter 2), the clusters of phenol with one and two argon atoms (chapter 3), O-toluidine (chapter 4), the 7-azaindole one and two water clusters (chapter 5), the phenol dimer (chapter 6) and benzimidazole (chapter 7).'
