Comparative structural study of the disorderedMCd6quasicrystal approximants

Antiferromagnetic order in the quasicrystal approximant Cd6Tb studied by x-ray resonant magnetic scattering

“…Therefore, the Tb ions can be viewed as occupying the second icosahedron shell of the Tsai clusters situated at the corner and body-centered positions, as described previously, 16,17 and shown in Fig. 1(a).…”

“…For instance, the magnetic rare earth sites in Cd-Mg-R correspond to the vertices of the triangular faces of an icosahedron contained within the Tsai-type clusters which form the backbone of the quasicrystal structure. 16,17 Thus situated, the geometrical frustration associated with triangular arrangements of spins follows naturally.…”

Structure determination of quasicrystals

“…sharp Bragg reflections) and a very good Cd/Yb X-ray contrast (Z Cd =48, Z Yb =70). Moreover in the same CdYb system and for very similar chemical compositions the 1/1 Cd 6 Yb [23,24] and 2/1 Cd 5.8 Yb cubic periodic approximants can be synthesised. The structure of these two phases has been solved, and can serve as a basis for the parent QC structure determination [23,24].…”

Crystal electric field excitations in the quasicrystal approximantTbCd6studied by inelastic neutron scattering

“…The quasicrystal approximants, RCd 6 (R = rare earth), 2,3 and related icosahedral quasicrystal phases, i-R-Cd, 4 form a set of model systems to explore how magnetism evolves from a conventional periodic lattice (approximant phase) to an aperiodic quasicrystal. Although TbCd 6 manifests long-range antiferromagnetic order (T N ∼ 22 K), [5][6][7] only spin-glass-like behavior is observed in i-Tb-Cd with a spin freezing temperature of T F = 6 K. 4,8 In fact, all of the known quasicrystals with local moments exhibit spin-glass-like ground states at low temperature.…”