Networks of icosahedra in the sodium-zinc-stannides Na{sub 16}Zn{sub 13.54}Sn{sub 13.46(5)}, Na{sub 22}Zn{sub 20}Sn{sub 19(1)}, and Na{sub 34}Zn{sub 66}Sn{sub 38(1)}

Journal Article · Wed Apr 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2008.12.023· OSTI ID:21370338

Kim, Sung-Jin ^[1]

---

1. Department of Chemistry, Technische Universitaet Muenchen, Lichtenbergstr. 4, D-85747 Garching (Germany)

The three new ternary phases Na{sub 16}Zn{sub 13.54}Sn{sub 13.46(5)} (I), Na{sub 22}Zn{sub 20}Sn{sub 19(1)} (II), and Na{sub 34}Zn{sub 66}Sn{sub 38(1)} (III) were obtained by direct fusion of the pure elements and characterized by single crystal X-ray diffraction experiments: I, Ibam, Z=8, a=27.401(1), b=16.100(1), c=18.431(1) A, R{sub 1}/wR{sub 2} (all data)=0.051/0.088; II, Pnma, Z=4, a=16.403(1), b=15.598(1), c=22.655(6) A, R{sub 1}/wR{sub 2} (all data)=0.038/0.071; III, R3-bar m, Z=3, a=16.956(1), c=36.861(1) A, R{sub 1}/wR{sub 2} (all data)=0.045/0.092. The structures consist of complex 3D cluster networks made of Zn and Sn atoms with the common motif of Kagome nets of icosahedra. Additionally to the new heteroatomic {l_brace}Zn{sub 12-x}Sn{sub x}{r_brace} icosahedra that are omnipresent, triangular units, cages, and pairs of triply fused icosahedra fill the cavities of the Kagome nets in compounds I, II, and III, respectively. Whereas I crystallizes in a new structure type, II and III have structural analogs in trielide chemistry. All three compounds closely approach the electron numbers expected for valence compounds according to the extended 8-N rule. The concept of achieving an isovalent situation to triel elements by combination of electron poorer and richer elements and the readily mixing of Zn and Sn allow the formation of icosahedral and triangular clusters without the participation of a group 13 element. - Graphical abstract: Three new compounds Na{sub 16}Zn{sub 13.54}Sn{sub 13.46(5)} (I), Na{sub 22}Zn{sub 20}Sn{sub 19(1)} (II), and Na{sub 34}Zn{sub 66}Sn{sub 38(1)} (III) were obtained from the elements and were characterized by single-crystal X-ray diffraction. Their structures have in common Kagome layers of {l_brace}Zn{sub 12-x}Sn{sub x}{r_brace} icosahedra. Additional building units, such as triangles, 15-atom spacer, and triply fused icosahedra fill the structures of I, II, and III, respectively. The structures and the electron requirements are discussed.

• OSTI ID: 21370338
• Journal Information: Journal of Solid State Chemistry, Vol. 182, Issue 4; Other Information: DOI: 10.1016/j.jssc.2008.12.023; PII: S0022-4596(08)00653-1; 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
37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
INTERMETALLIC COMPOUNDS
MONOCRYSTALS
ORTHORHOMBIC LATTICES
SODIUM ALLOYS
TIN ALLOYS
TRIGONAL LATTICES
X-RAY DIFFRACTION
ZINC ALLOYS
ALLOYS
COHERENT SCATTERING
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTALS
DIFFRACTION
SCATTERING