The nature of inter-atomic and inter-molecular interactions are key to a “bottom up” understanding of most aspects of matter, from solid state to biological systems. Traditionally these interactions can only be indirectly inferred from bulk (ensemble) measurements, or via modelling of samples of interest. High resolution scanning probe microscopy (SPM) offers one of the few routes available to directly access the local properties of matter at the single atom level, but until recently has been hampered by uncertainties related to the nature of the probing interaction – governed by the atomic scale properties of the end of the scanning probe tip.
In the last decade, significant progress has been made to solve these issues via the concept of functionalising probe tips with well defined molecular species and in-situ characterisation of the resultant tips. This has arisen in combination with technological developments allowing the measurement of not only electrical properties (as is common in scanning tunnelling microscopy (STM)), but also forces at the single bond level via low temperature non-contact atomic force microscopy (NC-AFM).
This project aims to explore the mapping of complex intermolecular interactions in three dimensions with sub-angstrom precision, and to use these outputs as calibration for high quality ab-initio modelling. Key to this program of work is an unprecedented level of control of the intermolecular junction formed by a functionalised probe tip and the molecular sample.
The outcome of this project will involve a step change in our ability to control and characterise matter at the single bond level, but more importantly will provide a hitherto unavailable source of fundamental information on the strength and shape of intermolecular potentials, which will provide a new method for parametrising computational models of intermolecular interactions, which are key drivers in understanding biological and pharmaceutical systems.
