The Ternary Lanthanoid Nickel Arsenides Tb12Ni30As21 and Dy12Ni30As21 with (La, Ce)12Rh30P21 Type Related Structure

✍ Scribed by Wolfgang Jeitschko; Ludger J. Terbüchte; Ute Ch. Rodewald

• Publisher: John Wiley and Sons
• Year: 2001
• Tongue: German
• Weight: 250 KB
• Volume: 627
• Category: Article
• ISSN: 0372-7874
• DOI: 10.1002/1521-3749(200112)627:12<2673::aid-zaac2673>3.0.co;2-m

✦ Synopsis

The title compounds were synthesized from the elements by reactions at high temperature. They crystallize with a hexagonal structure which was determined from single-crystal X-ray data of Dy 12 Ni 30 As 21 : P6 3 /m, Z = 1, a = 1698.5(5) pm, c = 387.7(1) pm, R = 0.053 for 797 F values and 69 variable parameters. It belongs to a large family of hexagonal structures with a metal to metalloid ratio of 2 : 1. In these hexagonal structures an ordered distribution of occupied atomic positions around the hexagonal 6 3 axis is possible only for refinements in space groups of lower symmetry. This is discussed for the present case and the very closely related structures reported for (La, Ce) 12 Rh 30 P 21 and Nd 3 Ni 7 P 5 .