title: Structural phase transitions on AgCuS stromeyerite mineral under compression.
abstract: The structural behavior of mineral Stromeyerite, AgCuS, has been studied by means of angle-dispersive X-ray diffraction measurements up to 13 GPa and ab initio total-energy calculations. Two high-pressure phase transitions are found at 1.4 and 5.7 GPa, from the initial distorted Ni(2)In-type phase (AuRbS-type, RP, space group Cmc2(1)) through an anti-PbClF-type phase (HP1, space group P4/nmm) to a monoclinic distortion of this latter phase (HP2, space group P2(1)/m). The collapse of the metal-metal interatomic distances at the RP-HP1 transition suggests a stronger metallic behavior of the high-pressure phase. The compressibility of the lattice parameters and the equation of state of the first pressure-induced phase have been experimentally determined. First-principles calculations present an overall agreement with the experimental results in terms of the high-pressure sequence and provide chemical insight into the AgCuS behavior under hydrostatic pressure.
authors.affiliation: Departamento de Química-Física I, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain. dsantamaria@quim.ucm.es
authors.forename: D
authors.initials: D
authors.lastname: Santamaria-Perez
authors.forename: A
authors.initials: A
authors.lastname: Morales-Garcia
authors.forename: D
authors.initials: D
authors.lastname: Martinez-Garcia
authors.forename: B
authors.initials: B
authors.lastname: Garcia-Domene
authors.forename: C
authors.initials: C
authors.lastname: Mühle
authors.forename: M
authors.initials: M
authors.lastname: Jansen