title: Al3AuIr: A New Compound in the Al-Au-Ir System.
abstract: A new ternary phase with a composition of Al3AuIr has been found in the Al-rich area of the Al-Au-Ir system. Differential thermal analysis indicates a melting point of 990 °C, and single-crystal X-ray diffraction measurements reveal that this ternary phase adopts a Ni2Al3 structure type (space group P3̅m1) with a = 4.2584(5) Å and c = 5.1991(7) Å. This compound is isostructural to the Al3Cu1.5Co0.5 phase also found in the Al-rich part of the Al-Cu-Co ternary diagram. Experimental evidence combined with ab initio calculations point toward an Al3AuIr phase stabilized by a Hume-Rothery mechanism. Quantum chemical calculations indicate two-center and multicenter interactions in the Al3AuIr phase. Layered distribution of two-center interactions separated by regions with four- and five-center bonds suggests a preferential cleavage of the material at puckered planes perpendicular to the [001] direction.
authors.affiliation: †Institut Jean Lamour (UMR7198 CNRS, Université de Lorraine), Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Joris
authors.initials: J
authors.lastname: Kadok
authors.affiliation: †Institut Jean Lamour (UMR7198 CNRS, Université de Lorraine), Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Marie-Cécile
authors.initials: MC
authors.lastname: de Weerd
authors.affiliation: †Institut Jean Lamour (UMR7198 CNRS, Université de Lorraine), Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Pascal
authors.initials: P
authors.lastname: Boulet
authors.affiliation: †Institut Jean Lamour (UMR7198 CNRS, Université de Lorraine), Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Émilie
authors.initials: É
authors.lastname: Gaudry
authors.affiliation: ‡Max-Planck-Institut für Chemische Physik fester Stoffe, Nöthnitzer Strasse 40, 01187 Dresden, Germany.
authors.forename: Yuri
authors.initials: Y
authors.lastname: Grin
authors.affiliation: †Institut Jean Lamour (UMR7198 CNRS, Université de Lorraine), Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Fournée
authors.affiliation: †Institut Jean Lamour (UMR7198 CNRS, Université de Lorraine), Parc de Saurupt, 54011 Nancy Cedex, France.
authors.forename: Julian
authors.initials: J
authors.lastname: Ledieu