TiNiSi structure

Co2Si (PbCl2), oP12, and TiNiSi, oP12, structural types. Orthorhombic, space group Puma, N. 62. 

Figure 7.34. Projection of four cells of the oP12-TiNiSi type structure.

The cell projection of the oP12-TiNiSi structure is shown in Fig. 7.34. 

The ternary variant TiNiSi type is also called E-phase structure. Many ternary compounds belonging to a MeTX formula (Me = rare earth metal, Ti, Hf, V, etc., T = transition metal of the Mn, Fe, Pt groups, X = Si, Ge, Sn, P, etc.) have this structure. Strukturbericht designation C23. 

Pr-Rh-Sb. Malik and Adroja (1991b) established a KHg2 type with a = 0.4596, b = 0.7391, c = 0.7848 for the PrRhSb compound by using X-ray powder diffraction of an arc melted alloy. The purities of the metals were better than 99.99%. Adroja et al. (1999) observed the TiNiSi structure type for the PrRhSbo.976 compound from metallographic analyses and powder diffraction. 

EuPdSb crystallizes with the TiNiSi type structure, a = 0.7627, b = 0.4695, c = 0.7925 (Malik and Adroja, 1991c powder X-ray diffraction data). Starting elements (Eu 4N, Pd 4N, Sb 4N) were arc melted under argon. 

Lattice parameters of the Cei xLa> RhSb alloys, TiNiSi type structure... 

Substitution of Ce by La in Cei LaxRhSb, x = 0.1-1.0, TiNiSi type structure (table 6) was investigated by Malik et al. (1995) in the course of studying of some of the physical properties of these phases. 

Lan] Landrum, G.A., Hoffmann, R., Evers, J., Boysen, H., The TiNiSi Family of Compounds Stmcture and Bonding , Inorg. Chem., 37(22), 5754-5763 (1998) (Crys. Structure, Experimental, 34)... 

The series CeTSn together with CeRhSb and the related pseudo-ternary compounds crystallize in a rather complex orthorhombic structure with the non-centrosymmetric space group Pn2ia (Higashi et al. 1993). This structure, which is shown in fig. 106 (left), is closely related to the e-TiNiSi structure. It forms puckered hexagonal Ni—Sn-Ni rings... 

An extended Zintl formirlation is also possible for Yb Mg Ge (Merlo et al. 1993) with TiNiSi-type structure. In contrast to YbLiGe, the ytterbium atoms in YbMgGe should not carry a magnetic moment and one should expect PauU paramagnetism or small temperatiure-independent paramagnetism (TIP), hr view of the missing magnetic data, this remains an open question. 

So far only three YbTAs arsenides are known (table 10). YbLiAs (Albering 1993, Albering et al. 1997) crystallizes with the TiNiSi type structure. In this arsenide, the lithium atoms occupy the typical transition-metal site and we observe puckered Lis Ass networks. 

DyCoSi is orthorhombic with the TiNiSi-type of structure Pnma, a = 6.819, b = 4.172 and c = 7.174 (X-ray powder data by Yarovets, 1978) for sample preparation and atomic parameters, see YNiSi. 

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