Understanding Spontaneous Dipole Alignment in Molecular Solids

Spontaneous dipole alignment in molecular solids is a novel, energetically unfavourable, phenomenon observed in ultrathin molecular films at cryogenic temperatures which gives rise to intense electric fields, exceeding 10^8 V m-1, percolating the films. The fields are observed directly by electrostatic potential measurements and indirectly by electric field induced frequency changes (i.e. vibrational Stark shifts) in the IR spectra of the films. The growth of these fields is both non-local and non-linear and remains poorly understood. We will extend our experimental studies to investigate new dipolar molecules characterising their electric fields as previously while undertaking structural studies by X-ray and neutron scattering methods. In parallel, we will develop molecular dynamics simulations of the deposition process in experimentally characterised systems (CO and N2O) using realistic intermolecular and interfacial potentials in an attempt to understand the origins of these fields during the film growth process. External collaborations with Field (Aarhus, Denmark), Moriarty (Nottingham, UK) and Nyman (Gothenburg, Sweden) are likely.

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You should have, or expect to receive, a First class or 2:1 MChem degree in Chemistry, or equivalent in a relevant related subject.

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