title: Structural diversity of sodium.
abstract: Sodium exhibits a pronounced minimum of the melting temperature at approximately 118 gigapascals and 300 kelvin. Using single-crystal high-pressure diffraction techniques, we found that the minimum of the sodium melting curve is associated with a concentration of seven different crystalline phases. Slight changes in pressure and/or temperature induce transitions between numerous structural modifications, several of which are highly complex. The complexity of the phase behavior above 100 gigapascals suggests extraordinary liquid and solid states of sodium at extreme conditions and has implications for other seemingly simple metals.
authors.affiliation: School of Physics and Centre for Science at Extreme Conditions, University of Edinburgh, Edinburgh EH9 3JZ, UK. e.gregoryanz@ed.ac.uk
authors.forename: Eugene
authors.initials: E
authors.lastname: Gregoryanz
authors.forename: Lars F
authors.initials: LF
authors.lastname: Lundegaard
authors.forename: Malcolm I
authors.initials: MI
authors.lastname: McMahon
authors.forename: Christophe
authors.initials: C
authors.lastname: Guillaume
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Nelmes
authors.forename: Mohamed
authors.initials: M
authors.lastname: Mezouar