Al15Ge4Ni3: A new intergrowth structure with Cu3Au- and CaF2-type building blocks

Thomas L. Reichmann, Isabella Jandl, Herta S. Effenberger, Peter Herzig, Klaus W. Richter (Korresp. Autor*in)

Veröffentlichungen: Beitrag in FachzeitschriftArtikelPeer Reviewed


The new ternary compound Al 15Ge 4Ni 32 in the system Al-Ge-Ni) was synthesized in single crystalline form by a special annealing procedure from samples located in the three phase fields [L+Al+τ 2] and [L+Ge+τ 2]. The crystal structure of Al 15Ge 4Ni 3 was determined by single-crystal X-ray diffraction. The compound crystallizes in a new structure type in space group I43m, Pearson Symbol cI88, cubic lattice parameter a=11.405(1) A˚. Phase diagram investigations indicate stoichiometric composition without considerable homogeneity range; τ 2 melts peritectically at T=444 °C. The crystal structure of Al 15Ge 4Ni 3 shows a unique combination of simple Cu 3Au- and CaF 2-type building blocks: a three dimensional network of CaF 2-type units, formed by Ni and Al atoms, is interspaced by clusters (Al 6Ge 8) resembling unit cells of the Cu 3Au-type. Both structural motifs are connected by Al-Ge bonds. The ground state energy of the compound was obtained by DFT calculations and the densities of states were analyzed in detail. In addition, electron density maps were calculated in four different sections through the unit cell using the full potential linearized augmented plane-wave (FLAPW) method. The bonding situation in Al 15Ge 4Ni 3 was discussed combining results from electronic calculations with the analysis of the coordination of atoms.

Seiten (von - bis)240-248
FachzeitschriftJournal of Solid State Chemistry
PublikationsstatusVeröffentlicht - Mai 2015

ÖFOS 2012

  • 104003 Anorganische Chemie
  • 104011 Materialchemie
  • 105113 Kristallographie