We investigated the metastable phase diagram of an ionic salt aqueous solution, LiCl:6D(2)O, at high pressure and low temperature by neutron diffraction measurements and computer simulations. We show that the presence of salt triggers a stepwise transformation, under annealing at high pressure, to a new very high-density amorphous form. The transition occurs abruptly at 120 K and 2 GPa, is reversible, and is characterized by a sizeable enthalpy release. Simulations suggest that the polyamorphic transition is linked to a local structural reorganization of water molecules around the Li ions.
Pressure-induced polyamorphism in salty water / Bove, L. E.; Klotz, S.; Philippe, J.; Saitta, A. M.. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - ELETTRONICO. - 106:12(2011), p. 125701. [10.1103/PhysRevLett.106.125701]