Phases in the Al-Yb-Zn system between 25 and 50 at% ytterbium

Journal Article · Tue Sep 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.06.012· OSTI ID:21370562

Mazzone, Donata ^[1]; Manfrinetti, Pietro ^[2]

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1. INSTM and Sezione di Chimica Inorganica, Dipartimento di Chimica e Chim. Ind., Universita di Genova, Via Dodecaneso 31, 16146 Genova (Italy)
2. Sezione di Chimica Fisica, Dipartimento di Chimica e Chim. Ind., Universita di Genova, Via Dodecaneso 31, 16146 Genova (Italy)

Phases YbZn{sub 1-x}Al{sub x}, YbZn{sub 2-x}Al{sub x} and YbZn{sub 3-x}Al{sub x} were studied by electron microprobe analysis and X-ray single crystal and powder methods. The compound YbZn{sub 0.8}Al{sub 0.2} crystallizes with the CsCl-type, a=3.635(2) A. Four phases were investigated by single crystal X-ray diffraction: YbZn{sub 0.996(6)}Al{sub 1.004(6)}, MgNi{sub 2}-type, P6{sub 3}/mmc, a=5.573(1), c=18.051(3) A, Z=8, wR2=0.040 and YbZn{sub 0.88(3)}Al{sub 1.12(3)}, MgCu{sub 2}-type, Fd3-barm, a=7.860(2) A, Z=8, wR2=0.060, both showing mixed Zn/Al occupancy; YbZn{sub 2.50(1)}Al{sub 0.50(1)}, CeNi{sub 3}-type, P6{sub 3}/mmc, a=5.496(1), c=17.336(2) A, Z=6, wR2=0.036 and YbZn{sub 1.92(2)}Al{sub 1.08(2)}, PuNi{sub 3}- or NbBe{sub 3}-type, R3-barm, a=5.499(1), c=26.134(5) A, Z=9, wR2=0.053, where the zinc atoms are ordered in the CaCu{sub 5} segment, while share the sites with aluminium in the Laves phase segment. In the pseudobinary section YbZn{sub 2-x}Al{sub x} four structures occur in sequence with increasing the electron concentration: CeCu{sub 2} or KHg{sub 2} (x=0-0.3), MgZn{sub 2} (x=0.33-0.54), MgNi{sub 2} (x=0.68-1.01) and MgCu{sub 2} (x=1.12-2). This sequence agrees with the results of first-principles calculations, already reported in the literature for other similar series. In the YbZn{sub 3-x}Al{sub x} section CeNi{sub 3}-type compounds occur with x=0.40-0.88 followed by PuNi{sub 3}-type compounds with x=0.92-1.10. The stability ranges of these phases are related to the valence electron concentration. - Graphical abstract: In the pseudobinary section YbZn{sub 2-x}Al{sub x} four structures occur in sequence on increasing the aluminium content: CeCu{sub 2} (or KHg{sub 2}), MgZn{sub 2}, MgNi{sub 2} and MgCu{sub 2}. Volumes per atom vs. composition are reported in the figure.

• OSTI ID: 21370562
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 9; Other Information: DOI: 10.1016/j.jssc.2009.06.012; PII: S0022-4596(09)00261-8; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
ELECTRON MICROPROBE ANALYSIS
HCP LATTICES
LAVES PHASES
MONOCRYSTALS
POTASSIUM COMPOUNDS
X-RAY DIFFRACTION
YTTERBIUM ALLOYS
ZINC ALLOYS
ALKALI METAL COMPOUNDS
ALLOYS
CHEMICAL ANALYSIS
COHERENT SCATTERING
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALS
DIFFRACTION
HEXAGONAL LATTICES
MICROANALYSIS
NONDESTRUCTIVE ANALYSIS
RARE EARTH ALLOYS
SCATTERING