Melting and simple liquids

Studies of simple liquids are fundamental in the development of our understanding of this state of matter, for their simple atomic and electronic structures make them more amenable to theoretical description at the microscopic level. In particular, they are considered benchmark systems for ab initio theoretical methods. The interest in the liquid phase of light molecular compounds also largely stems from their geophysical and astrophysical relevance.

Our activity on simple molecular fluids under extreme P-T conditions has seen a strong development in the last years. First, in the framework of the ANR project MOFLEX (PI: F. Datchi), in collaboration with CEA and ESRF, a large effort has been put into developing innovative techniques for structural and vibrational measurements under extreme P-T. The latter, added to the future upgrade of ESRF-ID27, allow us to foresee a rich experimental program in the next years. Second, in the framework of the International ANR project PAX (PI: L.E. Bove), in collaboration with the Innsbruck University, and the ILL long-term project, the development of the quasi-elastic neutron scattering technique at high pressures (HP-QENS patent) has opened new access to the diffusive and tunnelling dynamics of the proton in hydrogenate systems at high P-T. This represents an important outcome for the international neutron community, in particular in view of the incoming operation of the European spallation source.