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

Autor(en)
Thomas L. Reichmann, Isabella Jandl, Herta S. Effenberger, Peter Herzig, Klaus W. Richter
Abstrakt

The new ternary compound Al

15Ge

4Ni

3

2 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.

Organisation(en)
Institut für Funktionelle Materialien und Katalyse, Institut für Mineralogie und Kristallographie, Institut für Physikalische Chemie, Core Facility für Kristallstrukturanalyse
Journal
Journal of Solid State Chemistry
Band
225
Seiten
240-248
Anzahl der Seiten
9
ISSN
0022-4596
DOI
https://doi.org/10.1016/j.jssc.2014.12.020
Publikationsdatum
05-2015
Peer-reviewed
Ja
ÖFOS 2012
104003 Anorganische Chemie, 104011 Materialchemie, 105113 Kristallographie
Schlagwörter
ASJC Scopus Sachgebiete
Electronic, Optical and Magnetic Materials, Condensed Matter Physics, Ceramics and Composites, Materials Chemistry, Inorganic Chemistry, Physical and Theoretical Chemistry
Link zum Portal
https://ucrisportal.univie.ac.at/de/publications/365a77cf-d1be-4949-b90a-b2b5a90b3984