Nb28Ni33.5Sb12.5, a New Representative of the X-phase

Phase Relations in the Nb-Ni-Sb System

“…1. The only ternary compound in the system is Nb 28 Ni 33.5 Sb 12.5 (new structure type) [1]. To determine the composition region of this phase, we prepared samples with constant Nb and Sb contents, differing in composition from the ternary compound by 2 mol %.…”

Variants of the X-phase in the Mn–Co–Ge system

“…Detailed crystal structure chemistry for the previously studied representatives of the Mn 14 (Mn 0.11 Co 0.64 Si 0.25 ) 23 structure type are presented elsewhere (Yarmolyuk et al, 1970;Manor et al, 1972;Wang & Mar, 2001). In this work, two crystals of similar composition were studied with the aim of comparing the ordering/disordering of the atoms in the structure.…”

“…U eq is defined as one-third of the trace of the orthogonalized U ij tensor. For Mn 14.89 (5) Co 15.48 (4) Ge 6.62 (2) , M1 and M3 are 0.876 (12)Co + 0.124 (12)Mn and 0.90Co + 0.10Mn, respectively, and M2 = 0.594 (5)Co + 0.406 5 (Yarmolyuk et al, 1970), Mn 16.46 Co 14.80 Si 5.75 (Manor et al, 1972) and Nb 14 Ni 16.78 Sb 6.22 (Wang & Mar, 2001)] of the X-phase with the Mn 14 (Mn 0.11 -Co 0.64 Si 0.25 ) 23 structure type. In all cases, the Mn atoms occupied seven independent positions (in the case of Nb 14 Ni 16.78 Sb 6.22 , the Nb atoms occupy the same positions instead).…”

“…There has been some discussion as to whether the structure is instead the Y-phase (Manor et al, 1972;Gupta, 2006); the similarity of the diffraction patterns indicates that they might be the same phase with a large homogeneity region. The second system reported in 2001 is composed of Nb-Ni-Sb (Wang & Mar, 2001) and was reported as the Nb 28 Ni 33.5 Sb 12.5 [Nb 14 Ni 16.75 Sb 6.25 or Nb 14 (Ni 0.728 Sb 0.272 ) 23 ] ternary compound, which crystalized in the X-phase structure type.…”

“…There has been some discussion as to whether the structure is instead the Y-phase (Manor et al, 1972;Gupta, 2006); the similarity of the diffraction patterns indicates that they might be the same phase with a large homogeneity region. The second system reported in 2001 is composed of Nb-Ni-Sb (Wang & Mar, 2001) In this article, the syntheses and crystal structures of two new Mn-Co-Ge compounds, representatives of the X-phase, will be discussed.…”