Table 3. Stoichiometries of the Ho2Ni1–xT1+x Phases with T = Si and Ge Determined from EDX and Rietveld Refinements, along with the Refined Lattice Parameters, Unit Cell Volumes, and Volume Contraction in Formation of the Compounds {ΔV % = [(Vobs – Vcalc)/Vcalc] × 100}.
| composition
[atom %] |
lattice
parameters [Å] |
||||||||
|---|---|---|---|---|---|---|---|---|---|
| nominal (of the sample) | EDX (of the main phase) | chemical formula (EDX data) | chemical formula (from Rietveld) | composition in atom % (from Rietveld) | a | b | c | Vobs [Å3] | ΔV % |
| Ho50Ni18.3Si31.7 | Ho50(1)Ni18.5(1)Si31.5(1) | Ho2.01(4)Ni0.74(4)Si1.26(4) | Ho2Ni0.750(1)Si1.250(1) | Ho50Ni18.75(2)Si31.25(2) | 14.9136(1) | 4.0986(1) | 11.0688(1) | 676.571(3) | –11.41 |
| Ho50Ni20Si30 | Ho50(1)Ni20(1)Si30(1) | Ho2.02(4)Ni0.80(4)Si1.20(4) | Ho2Ni0.846(1)Si1.154(1) | Ho50Ni21.15(2)Si28.85(2) | 14.8988(1) | 4.0996(1) | 11.0606(1) | 675.579(2) | –10.72 |
| Ho50Ni25Si25 | Ho50(1)Ni22(1)Si28(1) | Ho2.00(4)Ni0.88(4)Si1.12(4) | Ho2Ni0.922(3)Si1.078(3) | Ho50Ni23.05(8)Si26.95(8) | 14.8798(1) | 4.0995(1) | 11.0550(1) | 674.349(3) | –10.37 |
| Ho50Ni18.3Ge31.7 | Ho51(1)Ni19(1)Ge30(1) | Ho2.04(4)Ni0.76(4)Ge1.20(4) | Ho2Ni0.799(1)Ge1.201(1) | Ho50Ni19.98(2)Ge30.02(2) | 15.0138(1) | 4.1484(1) | 11.0753(1) | 689.804(9) | –12.16 |
| Ho50Ni20Ge30 | Ho50(1)Ni20(1)Ge30(1) | Ho2.00(4)Ni0.80(4)Ge1.20(4) | Ho2Ni0.804(1)Ge1.196(1) | Ho50Ni20.11(1)Ge29.89(1) | 15.0054(1) | 4.1483(1) | 11.0719(1) | 689.191(5) | –12.19 |
| Ho50Ni25Ge25 | Ho50(1)Ni20(1)Ge30(1) | Ho2.00(4)Ni0.80(4)Ge1.20(4) | Ho2Ni0.810(1)Ge1.190(1) | Ho50Ni20.25(2)Ge29.75(2) | 14.9824(1) | 4.1468(1) | 11.0696(1) | 687.748(7) | –12.31 |