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Preparation and Crystal Structures of Ternary Rare Earth Osmium Gallides Ln OsGa 3 ( Ln = Gd—Tm) and Ln OsGa 3 ( Ln = La—Nd)
Author(s) -
Schlüter Martin,
Jeitschko Wolfgang
Publication year - 2002
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 - 10.1002/1521-3749(200207)628:7<1505::aid-zaac1505>3.0.co;2-3
Subject(s) - osmium , crystallography , rare earth , chemistry , crystal structure , ternary operation , diffractometer , structure type , hexagonal crystal system , mineralogy , ruthenium , biochemistry , computer science , programming language , catalysis
The title compounds were prepared from the elemental components at high temperatures. The compounds Ln OsGa 3 crystallize with the cubic TmRuGa 3 type structure which was refined from four‐circle X‐ray diffractometer data of TbOsGa 3 : Pm 3¯ m , Z = 3, a = 640.8(1) pm, R = 0.014 for 173 structure factors and 10 variable parameters. The other gallides crystallize with a new structure type which was determined from single‐crystal X‐ray data of CeOsGa 4 : Pmma , Z = 6, a = 963.9(2) pm, b = 880.1(1) pm, c = 767.0(1) pm, R = 0.030 for 744 F values and 56 variables. The structure may be considered as consisting of two kinds of alternating layers, although bonding within and between the layers is of similar strength. One kind of layers ( A ) is slightly puckered, two‐dimensionally infinite, hexagonal close packed, with the composition OsGa 3 ; the other kind of layers ( B ) is planar with the composition CeGa. The structure is closely related to that of Y 2 Co 3 Ga 9 where the corresponding layers have the compositions Co 3 Ga 6 ( A ) and Y 2 Ga 3 ( B ).