Metastable Solid Solution with Nepheline-type Structure in the CaO–Al2O3–SiO2System

ABSTRACTWe present a comparative study (by 1.8 MeV 4He+ ion channeling) of virgin, self and Eu implanted single crystals of nickel, under irradiation with single ruby laser pulses. The as implanted Eu is nearly non-substitutional and remains so, even after laser treatment. The comparative defect dechanneling behaviour provides explicit evidence of defect-impurity interaction which may be suppressing the formation of an expected metastable solid solution in the Eu-Ni system, which possesses miscibility in the liquid phase. A clear surface Eu peak appears at 2.1 J/cm2.

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The solid solution TbNiIn1−x Ga x

Zeitschrift für Naturforschung B ◽

10.1515/znb-2021-0167 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Myroslava Horiacha ◽

Galyna Nychyporuk ◽

Rainer Pöttgen ◽

Vasyl Zaremba

Keyword(s):

Solid Solution ◽

Unit Cell ◽

Type Structure ◽

X Ray Diffraction ◽

Unit Cell Parameters ◽

Space Group ◽

X Ray ◽

Cell Parameters ◽

Structure Space ◽

Arc Melting

Abstract Phase formation in the solid solution TbNiIn1−x Ga x at 873 K was investigated in the full concentration range by means of powder X-ray diffraction and EDX analysis. The samples were synthesized by arc-melting of the pure metals with subsequent annealing at 873 K for one month. The influence of the substitution of indium by gallium on the type of structure and solubility was studied. The solubility ranges have been determined and changes of the unit cell parameters were calculated on the basis of powder X-ray diffraction data: TbNiIn1–0.4Ga0–0.6 (ZrNiAl-type structure, space group P 6 ‾ 2 m $P‾{6}2m$ , a = 0.74461(8)–0.72711(17) and c = 0.37976(5)–0.37469(8) nm); TbNiIn0.2–0Ga0.8–1.0 (TiNiSi-type structure, space group Pnma, а = 0.68950(11)–0.68830(12), b = 0.43053(9)–0.42974(6), с = 0.74186(10)–0.73486(13) nm). The crystal structures of TbNiGa (TiNiSi type, Pnma, a = 0.69140(5), b = 0.43047(7), c = 0.73553(8) nm, wR2=0.0414, 525 F 2 values, 21 variables), TbNiIn0.83(1)Ga0.17(1) (ZrNiAl type, P 6 ‾ 2 m $P‾{6}2m$ , a = 0.74043(6), c = 0.37789(3) nm, wR2 = 0.0293, 322 F 2 values, 16 variables) and TbNiIn0.12(2)Ga0.88(2) (TiNiSi type, Pnma, a = 0.69124(6), b = 0.43134(9), c = 0.74232(11) nm, wR2 = 0.0495, 516 F 2 values, 21 variables) have been determined. The characteristics of the solid solutions and the variations of the unit cell parameters are briefly discussed.

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Solid solutions in the system Ag2S–Ag2Se

Journal of Materials Research ◽

10.1557/jmr.1992.2219 ◽

1992 ◽

Vol 7 (8) ◽

pp. 2219-2224 ◽

Cited By ~ 16

Author(s):

N.E. Pingitore ◽

B.F. Ponce ◽

M.P. Eastman ◽

F. Moreno ◽

C. Podpora

Keyword(s):

Solid Solution ◽

Solid Solutions ◽

Type Structure ◽

Solid Solution Series ◽

X Ray Diffraction ◽

Compositional Gradient ◽

X Ray ◽

Optical Electron ◽

Discrete Phase ◽

Diffraction Peaks

Optical, electron microprobe, and x-ray diffraction analysis of 88 samples of various compositions between Ag2S and Ag2Se synthesized at high temperature in sealed quartz tubing indicates the presence of two solid-solution series in this system at ambient (room) conditions. One series extends from Ag2S to approximately Ag2S0.4Se0.7 and has the Ag2S-III-type structure (monoclinic). The second series ranges from Ag2S0.3Se0.7 to Ag2Se and is characterized by the Ag2Se-II-type structure (orthorhombic). Members of both series, in appropriate proportions, characterize the apparent compositional gap between the two solid solutions. Gradual shifts in the locations of the x-ray diffraction peaks along the compositional gradient of each solid solution revealed an expansion of the d-spacing as the larger Se ion was substituted for S in the Ag2S-III-type structure and a contraction as S was substituted for Se in the Ag2Se-II-type structure. The reported discrete phase, Ag4SSe (aguilarite, orthorhombic), appears to be simply a member of the monoclinic Ag2S-III-type solid solution.

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