Intermetallics La11Ru2Al6 and Ce11Ru2Al6
with a new structure type
Chem.
Met. Alloys 3
(2010) 101-107
https://doi.org/10.30970/cma3.0126
E.V. MURASHOVA, A.I. TURSINA, Zh.M. KURENBAEVA, H. NOËL, Y.D. SEROPEGIN
The crystal structures of RE11Ru2Al6 (RE = La, Ce) were determined from
single-crystal X-ray diffraction at room temperature. The compounds are isostructural and belong to a new structural type:
orthorhombic space group Pbam, Z =
2, a = 14.619(2),
14.0799(14) Å, b = 15.705(3), 15.4879(16) Å,
c = 4.4866(7), 4.4685(4) Å, respectively, Pearson symbol oP38. An interesting feature of the Ce11Ru2Al6
structure is the formation of short Ce-Ru distances
of 2.4404(8) Å in one of the six crystallographically independent Ce‑polyhedra,
whereas in the La11Ru2Al6 structure the La-Ru distances are only slightly shorter than the sum of the
covalent radii of La and Ru (2.7033(8) Å).
Near-neighbor coordination of the
Ru1 atoms in a) La11Ru2Al6; b) Ce11Ru2Al6.
Keywords
Rare-earth intermetallics
/ Crystal structure / Crystal chemistry of intermetallics