Crossover between tetrahedral and hexagonal structures in liquid water

CHARA OSVALDO; MCCARTHY ANDRÉS NORMAN; GRIGERA JOSÉ RAÚL

PHYSICS LETTERS A

ELSEVIER SCIENCE BV

Año: 2011 vol. 375 p. 572 - 576

0375-9601

It is widely accepted that liquid water structure is comprised of two closely interweaved components; i.e. tetrahedral (low density) and hexagonal (high density) structures. The relative amount of these components is temperature and pressure dependent. We propose an order parameter, based on the radial distribution function, that quantifies the relative structural composition at any defined temperature and pressure, thus establishing the crossover point in structural dominance. At 300 K this point lies close to 2 kbar, pressure at which water looses most of its ‘anomalous’ properties.