The short hydrogen bond in molecular materials: neutron diffraction and complementary studies

Experimental studies of a range of molecular materials containing short, strong hydrogen bonding motifs are presented, with a particular focus on the determination of the hydrogen atom parameters in these materials under non-ambient and varying external conditions. Various experimental techniques have been developed and exploited, including the implementation of single crystal neutron diffraction on single crystals at pressures of up to 5 kbar and temperatures down to 30 K, the use of a multiple-crystal technique to facilitate data collection, and the exploitation of X-ray methods based on the imaging potential of Fourier techniques on evolving structures which have proven to be unexpectedly valuable in this context. The parallel application of advanced computational methods to the understanding of molecular structure in the solid state has also formed an important strand of this work. The power of modern neutron single crystal diffraction in structural studies of this nature is emphasised.