Ternary systems Sr-{l_brace}Ni,Cu{r_brace}-Si: Phase equilibria and crystal structure of ternary phases

Journal Article · Mon Mar 15 04:00:00 EDT 2010 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.12.023· OSTI ID:21372521

Nasir, Navida; Melnychenko-Koblyuk, Nataliya; Grytsiv, Andriy ^[1]; Rogl, Peter ^[1]; Giester, Gerald ^[2]; Wosik, Jaroslaw; Nauer, Gerhard E ^[3]

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1. Institute of Physical Chemistry, University of Vienna, A-1090 Wien (Austria)
2. Institute of Mineralogy and Crystallography, University of Vienna, Althanstrasse 14, A-1090 Wien (Austria)
3. CEST-Kompetenzzentrum fuer elektrochemische Oberflaechentechnologie GmbH Victor-Kaplan-Strasse 2, A-2700 Wr. Neustadt (Austria)

Phase relations were established in the Sr-poor part of the ternary systems Sr-Ni-Si (900 deg. C) and Sr-Cu-Si (800 deg. C) by light optical microscopy, electron probe microanalysis and X-ray diffraction on as cast and annealed alloys. Two new ternary compounds SrNiSi{sub 3} (BaNiSn{sub 3}-type) and SrNi{sub 9-x}Si{sub 4+x} (own-type) were found in the Sr-Ni-Si system along with previously reported Sr(Ni{sub x}Si{sub 1-x}){sub 2} (AlB{sub 2}-type). The crystal structure of SrNi{sub 9-x}Si{sub 4+x} (own-type, x=2.7, a=0.78998(3), c=1.1337(2) nm; space group P4/nbm) was determined from X-ray single crystal counter to be a low symmetry derivative of the cubic, parent NaZn{sub 13}-type. At higher Si-content X-ray Rietveld refinements reveal the formation of a vacant site (square) corresponding to a formula SrNi{sub 5.5}Si{sub 6.5}square{sub 1.0}. Phase equilibria in the Sr-Cu-Si system are characterized by the compounds SrCu{sub 2-x}Si{sub 2+x} (ThCr{sub 2}Si{sub 2}-type), Sr(Cu{sub x}Si{sub 1-x}){sub 2} (AlB{sub 2}-type), SrCu{sub 9-x}Si{sub 4+x} (0<=x<=1.0; CeNi{sub 8.5}Si{sub 4.5}-type) and SrCu{sub 13-x}Si{sub x} (4<=x<=1.8; NaZn{sub 13}-type). The latter two structure types appear within a continuous solid solution. Neither a type-I nor a type-IX clathrate compound was encountered in the Sr-{l_brace}Cu,Ni{r_brace}-Si systems. Structural details are furthermore given for about 14 new ternary compounds from related alloy systems with Ba. - Graphical abstract: The crystal structure of SrNi{sub 9-x}Si{sub 4+x} (own-type, x=2.7, a=0.78998(3), c=1.1337(2) nm; space group P4/nbm) was determined from X-ray single crystal counter to be a low symmetry derivative of the cubic, parent NaZn{sub 13}-type and is related to CeNi{sub 8.5}Si{sub 4.5}-type.

• OSTI ID: 21372521
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 3 Vol. 183; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALLOY SYSTEMS
ALLOYS
ANNEALING
CHEMICAL ANALYSIS
CLATHRATES
COHERENT SCATTERING
COPPER ALLOYS
CRYSTAL STRUCTURE
CRYSTALS
DIAGRAMS
DIFFRACTION
DISPERSIONS
ELECTRON MICROPROBE ANALYSIS
HEAT TREATMENTS
HOMOGENEOUS MIXTURES
INFORMATION
INTERMETALLIC COMPOUNDS
MICROANALYSIS
MICROSCOPY
MIXTURES
MONOCRYSTALS
NICKEL ALLOYS
NONDESTRUCTIVE ANALYSIS
OPTICAL MICROSCOPY
PHASE DIAGRAMS
SCATTERING
SILICON ALLOYS
SOLID SOLUTIONS
SOLUTIONS
SPACE GROUPS
STRONTIUM ALLOYS
SYMMETRY GROUPS
TEMPERATURE RANGE
TEMPERATURE RANGE 1000-4000 K
TRANSITION ELEMENT ALLOYS
X-RAY DIFFRACTION