Syntheses and crystal structures of Y7Co6Sn23 and RE5Co6Sn18 (RE=Sc, Ho)

Crystal structure and superconducting properties of Sc5Ir6Sn18

“…They are separated from each other by an energy gap of −0.7 eV. The low-lying states are mainly due to Sn5 s electrons with a small admixture of Ir5 d and Sc4 s, while the high-energy states are dominated by Ir5 d states hybridized with Sn5 p and Sc4 s. Similar features of the electronic structure are reported for Sc 5 Co 6 Sn 18 [19].…”

“…B 11 = 0.85(1), B 22 = 2.24(2), B 33 = 2.12(1) for Sn3 in 16e and B 11 = 2.83(2), B 22 = 0.82(1), B 33 = 0.76(2) for Sn5 in 32g). Here it should be noted, that both problems are well known for '5-6-18' compounds and have been reported for the Tb 5 Rh 6 Sn 18 -prototype [1], RCo 6 Sn 18 (R = Sc, Ho) [18,19] etc. Normally, such random orientations of atomic displacement elipsoids are Since the structural motifs of Sc 5 Ir 6 Sn 18 and Tb 5 Rh 6 Sn 18 prototype are the same (the latter can be also considered as an averaged structure), the refined structure without splits was used for structural discussion (figures 2(b) and (c)).…”

“…Normally, such random orientations of atomic displacement elipsoids are Since the structural motifs of Sc 5 Ir 6 Sn 18 and Tb 5 Rh 6 Sn 18 prototype are the same (the latter can be also considered as an averaged structure), the refined structure without splits was used for structural discussion (figures 2(b) and (c)). Up to now the structure of compounds crystallizing with Tb 5 Rh 6 Sn 18 type were considered as an array of corner-sharing trigonal prisms [TSn 6 ] with intercalated [RSn 12 ] cuboctahedra [18,19] (T = transition d-metal, R = Sc, Y or rare-earth atom). Such a structural motif is also observed for the primitive cubic Yb 3 Rh 4 Sn 13 structure type also known as the Remeika phase [2,17], therefore the relation between these types is frequently discussed in the literature.…”

“…Presently, a complete refinement of single-crystal XRD data is known only for Sc 5 Co 6 Sn 18 and it is characterized by unphysical anisotropies of thermal displacements (e.g. U 33 ≈ 4U 11 for the Sn1-atom; U 11 ≈ 4U 22 for Sn2; U 11 = 5U 22 for Sn3 etc [18,19]). This can be an indication of a lower symmetry and/or splitting (i.e.…”

Crystal structure, chemical bonding, and electrical and thermal transport in Sc5Rh6Sn18

“…the (Sn 1−x Tb x )Tb 4 Rh 6 Sn 18 composition]. Later studies showed this structure type to be characterized either by unphysical anisotropies of thermal displacements, as in the case of Sc 5 Co 6 Sn 18 11,12 or by numerous splits of crystallographic positions occupied by Sn-atoms (Sc 5 Ir 6 Sn 18 13 ). The crystal structure of Sc 5 Rh 6 Sn 18 has never been refined up to now.…”