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Crystal structure of the new ternary antimonide Y 3 Ni 6 Sb 5 was investigated using X-ray single crystal data: own type of structure, space group P 2 1 / m , a = 1.06358(6) nm, b = 0.42030(3) nm, c = 1.26520(9), β = 113.326(3)°, Z = 2, R F = 0.055, wR F = 0.063 for 1341 independent reflections and 98 variable parameters. Isotypic compounds Gd 3 Ni 6 Sb 5 and Tb 3 Ni 6 Sb 5 were synthesized. Magnetic and electric transport properties were studied in the temperature range above 5 K. Y 3 Ni 6 Sb 5 is a temperature independent Pauli type paramagnet. The Gd 3 Ni 6 Sb 5 compound orders ferromagnetically at T C = 8 K, whereas the Tb 3 Ni 6 Sb 5 homologue is an antiferromagnet at T N –5 K. The onset of magnetic ordering is also proved by the electrical resistivity measurements. The analysis of the resistivity, ρ ( T ), measurements for Y 3 Ni 6 Sb 5 resulted in a Debye temperature Θ D = 135 K.

The interaction between the components of the ternary Y–Ni–P system has been investigated by means of electron probe microanalysis, X-ray phase and structure analyses, and the isothermal section of the phase diagram at 1070 K has been constructed for the first time. Existence of the earlier reported eight ternary phosphides of yttrium and nickel was confirmed, among them seven ternaries are daltonide compounds: YNi4P2 (ZrFe4Si2-type structure), Y2Ni12P7 (Zr2Fe12P7-type structure), Y6Ni20P13 (Zr6Ni20P13-type structure), Y6Ni14.9P10.18 (own structure type), Y20Ni42P30.34 (Sm20Ni41.6P30-type structure), Y15Ni28P21 (Tb15Ni28P21-type structure), and YNiP (Tb1−xNiP-type structure), whereas YNi1.66−1.78P2 (ThCr2Si2-type structure) is a berthollide compound with small homogeneity range. The crystal structures of the some ternary phosphides have been determined by X-ray powder diffraction (YNi4P2 and YNi1.66−1.78P2) and single crystal diffraction (Y2Ni12P7) techniques.

The new phase ω1-Mn6Ga29 was synthesised in single-crystal form from the elements applying the high-temperature centrifugation-aided filtration technique. The crystal structure was determined using diffraction data collected from a twinned specimen: a new prototype, space group P 1 ¯ ; a=6.3114(2) A, b=9.9557(3) A, c=18.920(1) A, α=90.473(1)°, β=90.847(1)°, γ=90.396(1)°; R1=0.047, wR2=0.117 for 317 variable parameters and 7346 observed reflections; twinning matrix 0 0 – 1 3 , 0 −1 0, −3 0 0; twin domains ratio 0.830(3):0.170. All manganese atoms in the crystal structure of ω1-Mn6Ga29 are coordinated exclusively by Ga forming distorted tetragonal antiprisms. The monocapped [MnGa8+1] antiprisms condense into pairs by sharing their pseudo-quadratic faces and are interconnected via common apexes and edges to form a 3D framework. The relationship between the crystal structures of ω1-Mn6Ga29 and CuAl2, α-, β-CoSn3, PtSn4, Ti4MnBi2, PdGa5, Rh3Ga16, Rh4Ga21, Al7FeCu2, Co2Al9, and RhBi4 is discussed.

The interaction between components in the Zr–Ti–P system in the range of up to 67 at.% P was analyzed and the isothermal section diagram at 1070 K was constructed from X-ray structural and EDS analysis. Solid substitutional solutions based on the binary phosphides M 3 P with the Ti 3 P-type structure (Ti 3.0−2.3 Zr 0−0.7 P and Zr 3.0−2.5 Ti 0−0.5 P) were found. The phosphide (Ti,Zr) 2 P with the Co 2 Si-type structure is homogeneous at the Zr 1.2−0.6 Ti 0.8−1.4 P composition. From powder X-ray diffraction methods, the crystal structure of ZrTiP 0.68 was shown to be of the Zn 3 Cu-type (space group P -6, a = 0.47600(1), c = 0.30038(1) nm, R I = 0.0444); HfTiP 0.68 is isostructural. These compounds are homogenous in the range Zr 1.0−1.5 Ti 1.0−0.5 P 0.68 and Hf 0.9−1.2 Ti 1.1−0.8 P 0.68 . From single-crystal methods, the structure of Zr 0.93 Ti 0.07 P 0.93 was determined to belong to the WC-type structure (space group P -6 m 2, a = 0.3004(2), c = 0.3117(3) nm, R F = 0.0228).

The new ternary pnictides Er{sub 12}Ni{sub 30}P{sub 21} and Er{sub 13}Ni{sub 25}As{sub 19} have been synthesized from the elements. They crystallize with hexagonal structures determined from single-crystal X-ray data for Er{sub 12}Ni{sub 30}P{sub 21} (space group P6{sub 3}/m, a=1.63900(3) nm, c=0.37573(1) nm, Z=1, R{sub F}=0.062 for 1574 F-values and 74 variable parameters), and for Er{sub 13}Ni{sub 25}As{sub 19} (Tm{sub 13}Ni{sub 25}As{sub 19}-type structure, space group P6-bar , a=1.6208(1) nm, c=0.38847(2) nm, Z=1, R{sub F}=0.026 for 1549 F-values and 116 variable parameters). These compounds belong to a large family of hexagonal structures with a metal-metalloid ratio of 2:1. HRTEM investigations were conducted to probe for local ordering of the disordered structure at the nanoscale. The magnetic properties of the phosphide Er{sub 12}Ni{sub 30}P{sub 21} have been studied in the temperature of range 2

The crystal structure of the new ternary antimonide Ho5GaSb3 has been determined from X-ray single-crystal data: space group Pnma, a = 7.9667(8), b = 15.128(2), c = 7.9616(8) Å , V = 959.5(3) Å3, Z = 4, RF = 0.059, Rw = 0.066 for 9020 reflections. The crystal structure of Ho5GaSb3 is a ternary derivative of the Sm5Ge4 structure type with partially ordered distribution of gallium and antimony atoms

Solid-state phase equilibria in the ternary systems Er-Ni-P and Er-Ni-As have been determined at 800 °C (region 0 - 67 at.% P or 0 - 50 at.% As) using X-ray diffraction, scanning electron microscopy and electron probe microanalysis. Eight ternary phosphides and six ternary arsenides have been synthesized, including several phases reported previously. The hexagonal structure of the new compound Er6Ni20P13, as determined from single-crystal X-ray data, exhibits a new structure type closely related to the Ho6Ni20P13 structure. Two other new phosphides, Er16Ni36P22 (Tb16Ni36P22- type) and Er20Ni42P30 (Sm20Ni41.6P30-type), have also been obtained at 800 °C. In the Er-Ni-As system, a new arsenide Er20Ni42As30 (Sm20Ni41.6P30-type) has been found in addition to known ternary phases. From X-ray powder data, the structures of the ternary arsenides ErNi4As2 (ZrFe4Si2-type) and Er2Ni12As7 (Zr2Fe12P7-type) have been refined by Rietveld methods. In the single crystal investigations, two other new phases Er12Ni30P21 [derived (La, Ce)12Rh30P21-type] and Er13Ni25As19 (Tm13Ni25As19-type) have been prepared by high-temperature annealing (1500 °C).

The solid state phase equilibria in the Er-rich region of the ternary Er–Ni–Sb system were determined at 1073 K using experimental techniques such as X-ray diffraction, scanning electron microscopy and electron probe microanalysis. In addition to the ternary phase Er5Ni2Sb previously reported, a new phase Er5Sb3−xNix (x = 0.48) was obtained, the structure of which was solved from X-ray single crystal data: space group Pnma, a = 1.17522(3) nm, b = 0.90437(3) nm, c = 0.79144(5) nm, R1 = 0.067, w R 2 = 0.070 . Moreover, for the first time, both modifications of the binary antimonide Er5Sb3 were obtained and their structures were studied from X-ray powder diffraction data. The low-temperature form belongs to the Mn5Si3 type: space group P63/mcm, a = 0.88062(4) nm, c = 0.62139(9) nm, RI = 0.074, Rp = 0.150, while the high-temperature form exhibits the β-Yb5Sb3 type: space group Pnma, a = 1.16897(3) nm, b = 0.91425(3) nm, c = 0.80217(2) nm, RI = 0.077, Rp = 0.125. According to these results, one can conclude that the substitution of antimony by nickel at 1073 K in the ternary phase Er5Sb3−xNix tends to stabilize the β-Yb5Sb3 type.

The structure of the ternary compound Nb5Si3 − x P0.5 + x (x = 0–0.5) is determined by single-crystal x-ray diffraction: sp. gr. P63 mc, a = 1.32350(5) nm, c = 0.52954(1) nm; R F = 0.028, R w = 0.081 for 547 reflections with F hkl > 4.0σ(F hkl ). Relations between the structure of Nb5Si3 − x P5 + x , the Mn5Si3 structure type, and its derivatives are discussed.

A new ternary compound of composition (V,Mo)84P49 (V3.2Mo8.8P7) is synthesized, and its structure is determined by single-crystal x-ray diffraction: a new structure type, sp. gr. Р6¯, a = 2.52015(3) nm, c = 0.330070(5) nm; RF = 0.054, Rw = 0.058 for 1894 independent reflections with Fhkl > 4.0σ(Fhkl). V3.2Mo8.8P7 is shown to contain mixed-occupancy (V, Mo) sites. The (V,Mo)84P49 and (Ti,Mo)36P21 structure types belong to a homologous series containing Cr12P7 as the n = 1 member.

A new ternary phosphide Y 6 Ni 15− x P 10+ y ( x =0.08, y =0.18) has been obtained in the Y–Ni–P system. Single crystals of this compound have been investigated on a Nonius KappaCCD X-ray diffractometer using Mo Kα radiation ( λ =0.071073 nm). The symmetry has been found to be hexagonal with space group P 6 3 / m and unit cell parameters a =1.6447(1) nm and c =0.37891(2) nm. Structure refinement including anisotropic displacement parameters led to the following results: R F =0.056 ( R w =0.047), GOF=1.060 for 558 reflections with F ( h k l ) > 4 σF ( h k l ). The ternary phosphide Y 6 Ni 15− x P 10+ y exhibits a new structure, which is derived from the Ce 6 Ni 15 P 10 and Nd 3 Ni 7 P 5 structure types.

A new ternary compound of composition Ti3.8Mo8.2P7.0 was identified, and its structure was determined by single-crystal x-ray diffraction: sp. gr. P 6¯, a= 1.67821(6) nm, c= 0.33196(2) nm; RF = 0.073 and Rw = 0.078 for 1359 independent reflections with Fhkl > 4σ(Fhkl ). The phase equilibria in the Ti–Mo–P system were refined in the region 0–25 mol % Ti and 33–40 mol % P.

The title compounds are prepared by arc melting of stoichiometric amounts of the elements followed by annealing (evacuated quartz tubes, 770 K, 720 h).

New ternary phosphide Ni7Si2P5 has been synthesized by direct interaction between powders of pure components at 1070 K and its crystal structure has been determined using X-ray single crystal method. The structure is of a new type with space group Pbcn (no. 60) and lattice constants as follows, a = 23.84(2) Å, b = 5.925(2) Å, c = 4.922(1) Å, Z = 4. The final residuals are RF = 0.048, Rw = 0.044 for 362 symmetry independent reflections (diffractometer KM-4, MoKα -radiation). Crystal structure of Ni7Si2P5 is closely related to Ni2SiP and Ni5Si2P3 structures which belong to the series of linear inhomogeneous structures M2m+2n X2m+2n (M and X correspond to metal and non-metal atoms, respectively) and are derivatives from the MnP-type structure.

The isothermal sections of the phase diagrams of the CeCuP ternary system at 670 K (region of 0–30 at.% P) and 1070 K (region of 30–75 at.% P) have been obtained by means of X-ray analysis. At the investigated temperatures two ternary Ce5Cu19P12 and CeCu1.09P1.87 compounds have been obtained and their crystal structures have been determined using X-ray single crystal data. The compound Ce5Cu19P12 has a crystal structure closely related to the Ho5Ni19P12-type, P 6 m with lattice parameters a = 12.690(1), c = 3.922(1) A , Z = 1, R F = 0.0535, R w = 0.0552 (diffractometer STOE STADI 4, Mo Kα radiation). The compound CeCu1.09P1.87 has a tetragonal BaAl4-derivative structure, I4/mmm with a = 3.918(1), c = 19.610(3) A , Z = 4, R F = 0.0483, R w = 0.0454 (diffractometer KM-4, Cu Kα radiation). Structural details of the obtained compounds and their relationships with known structures are discussed.

The isothermal section of the title system at 1070 K and up to 67 at.% P is characterized by XRD.

The new title compounds are prepared by reactions of stoichiometric mixtures of the elements (1100 °C for 3 d) followed by annealing at 1300—1500 °C for 48—72 h.

The title compounds are prepared by arc melting of the elements using a 2 at.% excess of Sb (700 °C, 240—360 h).

International audience; The ternary antimonides Ln3Pd8Sb4 (Ln=Y, Gd, Tb, Dy, Ho, Er, Tm) have been synthesized for the first time. The crystal structure of Er3Pd8Sb4 has been solved from the X-ray single crystal data: own type structure, space group Fm3¯m, a=1.3050(1) nm, RF=0.0484, RW=0.0524 for 17 free parameters and 401 reflections with F(hkl)>4σ(F). The structure of Er3Pd8Sb4 can be viewed as a ternary ordered version of the Sc11Ir4-type. The lattice parameters of the isotypic compounds Ln3Pd8Sb4 (Ln=Y, Gd, Tb, Dy, Ho, Tm) have been refined from the X-ray powder diffraction data. The magnetic and electrical properties of the compounds Ln3Pd8Sb4 (Ln=Tb, Ho, Er) have been studied down to 1.75 K. The Ho- and Er-based phases have been found to order antiferromagnetically at 2.5 and 2.0 K, respectively. For all three compounds, the magnetic susceptibility follows in the paramagnetic region the Curie-Weiss behavior with the effective magnetic moments close to the respective free trivalent ion values. All three antimonides studied exhibit metallic character of the electrical conductivity.

The crystal structure of the new ternary antimonide Ho5GaSb3 has been determined from X-ray single-crystal data: space group Pnma, a = 7.9667(8), b = 15.128(2), c = 7.9616(8) A, V = 959.5(3) A3, Z = 4, RF = 0.059, Rw = 0.066 for 9020 reflections. The crystal structure of Ho5GaSb3 is a ternary derivative of the Sm5Ge4 structure type with partially ordered distribution of gallium and antimony atoms.

Solid-state phase equilibria in the ternary systems Er-Ni-P and Er-Ni-As have been determined at 800 °C (region 0 - 67 at.% P or 0 - 50 at.% As) using X-ray diffraction, scanning electron microscopy and electron probe microanalysis. Eight ternary phosphides and six ternary arsenides have been synthesized, including several phases reported previously. The hexagonal structure of the new compound Er₆Ni₂₀P₁₃, as determined from single-crystal X-ray data, exhibits a new structure type closely related to the Ho₆Ni₂₀P₁₃ structure. Two other new phosphides, Er₁₆Ni₃₆P₂₂ (Tb₁₆Ni₃₆P₂₂- type) and Er₂₀Ni₄₂P₃₀ (Sm₂₀Ni₄₁.₆P₃₀-type), have also been obtained at 800 °C. In the Er-Ni-As system, a new arsenide Er₂₀Ni₄₂As₃₀ (Sm₂₀Ni₄₁.₆P₃₀-type) has been found in addition to known ternary phases. From X-ray powder data, the structures of the ternary arsenides ErNi₄As₂ (ZrFe₄Si₂-type) and Er₂Ni₁₂As₇ (Zr₂Fe₁₂P₇-type) have been refined by Rietveld methods. In the single crystal investigations, two other new phases Er₁₂Ni₃₀P₂₁ [derived (La, Ce)₁₂Rh₃₀P₂₁-type] and Er₁₃Ni₂₅As₁₉ (Tm₁₃Ni₂₅As₁₉-type) have been prepared by high-temperature annealing (1500 °C).

The solid state phase equilibria in the Er-rich region of the ternary Er–Ni–Sb system were determined at 1073 K using experimental techniques such as X-ray diffraction, scanning electron microscopy and electron probe microanalysis. In addition to the ternary phase Er5Ni2Sb previously reported, a new phase Er5Sb3−xNix (x = 0.48) was obtained, the structure of which was solved from X-ray single crystal data: space group Pnma, a = 1.17522(3) nm, b = 0.90437(3) nm, c = 0.79144(5) nm, R1 = 0.067, w R 2 = 0.070 . Moreover, for the first time, both modifications of the binary antimonide Er5Sb3 were obtained and their structures were studied from X-ray powder diffraction data. The low-temperature form belongs to the Mn5Si3 type: space group P63/mcm, a = 0.88062(4) nm, c = 0.62139(9) nm, RI = 0.074, Rp = 0.150, while the high-temperature form exhibits the β-Yb5Sb3 type: space group Pnma, a = 1.16897(3) nm, b = 0.91425(3) nm, c = 0.80217(2) nm, RI = 0.077, Rp = 0.125. According to these results, one can conclude that the substitution of antimony by nickel at 1073 K in the ternary phase Er5Sb3−xNix tends to stabilize the β-Yb5Sb3 type.

A new ternary phosphide Y 6 Ni 15− x P 10+ y ( x =0.08, y =0.18) has been obtained in the Y–Ni–P system. Single crystals of this compound have been investigated on a Nonius KappaCCD X-ray diffractometer using Mo Kα radiation ( λ =0.071073 nm). The symmetry has been found to be hexagonal with space group P 6 3 / m and unit cell parameters a =1.6447(1) nm and c =0.37891(2) nm. Structure refinement including anisotropic displacement parameters led to the following results: R F =0.056 ( R w =0.047), GOF=1.060 for 558 reflections with F ( h k l ) > 4 σF ( h k l ). The ternary phosphide Y 6 Ni 15− x P 10+ y exhibits a new structure, which is derived from the Ce 6 Ni 15 P 10 and Nd 3 Ni 7 P 5 structure types.

Single-crystal x-ray diffraction was used to determine the crystal structures of the ternary phosphides Zr2Mn12P7 (sp. gr. P63/m, a new structure type derived from the Zr2Fe12P7 type,a = 0.9348(2) nm, c = 0.35755(5) nm, R = 0.039, R w = 0.041) and (Mo,Mn)12P7 (sp. gr. P6¯ , a new structure type derived from the Cr12P7 type, a = 0.93242(4) nm,c= 0.33807(1) nm, R = 0.048, R w = 0.049).

The binary phosphide penta­nickel tetra­phosphide, Ni5P4, has been reinvestigated, leading to improved reliability factors than found previously [Elfstrom (1965), Acta Chem. Scand. 19, 1694–1704] and inclusion of anisotropic displacement parameters.