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Synthesis, Crystal Structures and Properties of the Zintl Phases Sr 2 ZnP 2 , Sr 2 ZnAs 2 , A 2 ZnSb 2 and A 2 ZnBi 2 ( A = Sr and Eu)
Author(s) -
Wilson Dereck K.,
Saparov Bayrammurad,
Bobev Svilen
Publication year - 2011
Publication title -
zeitschrift für anorganische und allgemeine chemie
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.354
H-Index - 66
eISSN - 1521-3749
pISSN - 0044-2313
DOI - 10.1002/zaac.201100177
Subject(s) - crystal structure , crystallography , intermetallic , zinc , stoichiometry , diffraction , x ray crystallography , space group , chemistry , magnetic susceptibility , hexagonal crystal system , formula unit , materials science , physics , alloy , optics , organic chemistry
The new intermetallic compounds Sr 2 ZnP 2 , Sr 2 ZnAs 2 , A 2 ZnSb 2 and A 2 ZnBi 2 ( A = Sr, Eu) have been synthesized from the corresponding elements through high‐temperature reactions using the flux‐growth method. Their structures have been established by single‐crystal and powder X‐ray diffraction. In all cases, the X‐ray diffraction patterns can be successfully indexed based on hexagonal cells in the space group P 6 3 / mmc (no. 194) with lattice parameters in the range a = 4.31–4.73 Å and c = 7.9–8.55 Å. The average structure can be described in the ZrBeSi type (Pearson symbol hP 6; 3 unique positions) with defects on the zinc site – structure refinements indicate that every second zinc position is vacant, i.e., their formula unit is A Zn 1– x Pn with x = 0.5( A = Sr, Eu; Pn = P, As, Sb, Bi). No stoichiometry breadth was observed, which could imply that a super‐structure with a long‐range order of the zinc vacancies is plausible and evidence for such was sought using electron diffraction. The results from these experiments, as well as magnetic susceptibility measurements and band structure calculations using the LMTO code are also discussed.