An Electron and X-Ray Diffraction Investigation of Ni1+xTe2 and Ni1+xSe2CdI2/NiAs Type Solid Solution Phases

doi:10.1006/jssc.2001.9309

Journal of Solid State Chemistry

Volume 161, Issue 2, 1 November 2001, Pages 266-273

https://doi.org/10.1006/jssc.2001.9309 Get rights and content

Abstract

The reported wide-range nonstoichiometric Ni_1+xTe₂, 0≤x≤0.83, and Ni_1+xSe₂, 0.57≤x≤0.92, CdI₂/NiAs structure type solid solution fields have been carefully reinvestigated via electron and X-ray powder diffraction to search for evidence of Ni/vacancy ordering and superstructure phases. In the case of telluride, evidence is thereby found for a Ni₃Te₄ superstructure phase attempting to condense out at x∼0.5 while, in the case of selenide, three quite distinct phases have been identified within the Ni_1+xSe₂ solid solution field. An intriguing characteristic honeycomb diffuse-intensity distribution has also been observed across the solid solution field in the case of the Ni_1+xTe₂ system. Its presence has been attributed to low frequency phonon modes along certain very specific directions of reciprocal space.

References (21)

S. Esmaeilzadeh et al.
J. Solid State Chem.
(2001)
R.L. Withers et al.
J. Solid State Chem.
(2000)
A.-K. Larsson et al.
J. Solid State Chem.
(1996)
S. Jobic et al.
J. Solid State Chem.
(1992)
E. Canadell et al.
J. Solid State Chem.
(1992)
W. Bensch et al.
J. Solid State Chem.
(1996)
Y. Hinatsu et al.
J. Solid State Chem.
(2000)
M. Hart
J. Crystal Growth
(1981)
T. Ohtani et al.
J. Solid State Chem.
(1983)
F. Brink et al.
J. Solid State Chem.
(2000)

There are more references available in the full text version of this article.

Cited by (19)

Scanning tunneling microscopy and spectroscopy of NiTe<inf>2</inf>
2022, Surface Science
Citation Excerpt :
The lattice parameters in regions with low defect density, as shown in Fig. 1b, are measured to be 3.82 ± 0.12 Å along the high-symmetry axes of the crystal. These values are in close agreement with previous measurements of the bulk lattice parameters and indicate cleaving reveals the (0001) surface [19,20]. Layer-to-layer heights measured at step edges are 4.83 ± 0.26 Å.
Nickel ditelluride is an unusual member of the transition metal dichalcogenide family which has garnered interest due to potential valley spin-polarized surface states near the Fermi level and the presence of Dirac nodes in its electronic band structure. In this work, exfoliation of bulk nickel ditelluride is performed under ultra-high vacuum in order to generate a clean surface for scanning tunneling microscopy and spectroscopy at 4.8 K. Multiple features in the observed electronic density of states are observed in the vicinity of the Fermi level and compared to calculated band structures to elucidate their origins. Our results are consistent with the presence of the spin-polarized surface states, yet indicate trivial states, which are close to the Fermi level, can interfere with their potential utility in spintronic applications.
Thermodynamic assessment of the Fe–Ni–Te system
2019, Calphad: Computer Coupling of Phase Diagrams and Thermochemistry
For the purpose of modeling internal corrosion of the stainless steel fuel pins in fast nuclear reactors, the present work presents a thermodynamic description of the Fe–Ni–Te system modeled via the Calphad method. The liquid phase was modeled using the ionic 2-sublattice liquid model. Only binary parameters were optimized in the $β 2$ , δ and τ solid phases, to fit the isothermal section at 600 $° C$ . The liquid did not require much adjustment from the extrapolation from the binary Fe–Te, Ni–Te and Fe–Ni systems. The paper presents a re-optimization of the Fe–Te liquid description in order to remove inverted liquid miscibility gaps at high temperatures. The resulting phase diagrams reproduce experimental isothermal sections well, and fits liquidus and solidus data very well. The description will be incorporated into the Thermodynamics of Advanced Fuels - International Database (TAF-ID). This will then be coupled with the Germinal system code to model the fission-product induced corrosion in nuclear fuel pins.
Thermodynamic assessment of the Fe-Te system. Part I: Experimental study
2019, Journal of Alloys and Compounds
A thermodynamic description of the Fe-Te system needs to be developed in order to model internal corrosion by fission products in fuel pins of Generation IV nuclear reactors. In preparation for a thermodynamic assessment of the system, an experimental study has been performed in order to clarify some unknown or conflicting phase diagram data. New phase diagram data have been obtained using Differential Thermal Analysis and isothermal heat treatments followed by electron microscopy with EDS and WDS analysis. The DTA analysis revealed new phase boundary data, and confirmed a very steep Fe-rich liquidus, supporting the possibility of a liquid miscibility gap in the Fe-FeTe region. The analyses also confirmed the probable eutectoid reaction $δ \to β + δ'$ at 523 $° C$ . The invariant arrests of the unknown $γ$ phase were consistent with information available in literature, but the phase was not identified via XRD of samples at its postulated composition. However, metallography of the samples revealed an unexpected microstructure pertaining to the $δ$ phase, which might be the $γ$ phase, and is discussed in this paper. The monoclinic space group $C 2 / m$ is proposed for the $δ$ phase based on XRD. The collected data will be used together with that available in literature to perform a thermodynamic Calphad assessment in a subsequent paper Part II: Thermodynamic modeling.
Novel magnetic properties of uniform NiTe<inf>x</inf> nanorods selectively synthesized by hydrothermal method
2017, Materials and Design
Citation Excerpt :
The (0 0 1) peak emerges in NiTe1.15 and gradually enhanced with x, implying NiTe2 appears in NiTex (x ≥ 1.15). This is different with the estimation of a continuous solid-solution phase between the compounds of NiTe and NiTe2 [27]. The similar crystal structure and close lattice parameters let NiTe and NiTe2 coexist.
NiTe_x nanorods (x = 1.00, 1.15, 1.33, 1.60, 1.80, 2.00) with average diameter of 150 nm have been selectively synthesized by a simple hydrothermal process. The nanorods with various x share similar hexagonal structure and morphology. NiTe nanorods present paramagnetic property at both high and low temperature while NiTe₂ nanorods exhibit a diamagnetic characteristic at high temperature and a paramagnetic behavior below 58 K. The magnetic moment reduces with the increase in tellurium content. The difference in magnetic behaviors of NiTe_x nanorods is mainly attributed to the competition between the diamagnetism and paramagnetism based on the experimental observation.
Phase equilibria and structural investigations of the general NiAs-type in the ternary system Ni-Sn-Te
2014, Intermetallics
Citation Excerpt :
Several authors, listed in the assessment of Lee and Nash [19], studied the lattice parameter variations throughout this phase field. Also, temperatures and compositions of the structural change from NiAs to CdI2 type were investigated by a number of authors [10,11,24,25]. In the ternary system Ni–Sn–Te Baranov et al. [30] found the new ternary compound Ni5.78SnTe2 and gave a tentative isothermal section at 540 °C as well.
The ternary system Ni–Sn–Te was investigated by means of light optical microscopy (LOM), powder X-ray diffraction (XRD), differential thermal analysis (DTA) and scanning electron microscopy (SEM) in combination with energy dispersive X-ray spectroscopy (EDX). Two isothermal sections at 600 and 800 °C were investigated experimentally. The two ternary compounds, Ni_5.78SnTe₂ (space group I4/mmm, Pearson symbol tI18) and Ni_3−xSnTe₂ (space group P6₃/mmc, Pearson symbol hP12), already known from literature, were confirmed, although Ni_3−xSnTe₂ was found only at 600 °C. At higher temperatures a continuous phase field of the general NiAs-type structure was discovered between NiTe_2−x and Ni₃Sn₂ HT. It ranges continuously from 34 to 63 at.% Ni, covering CdI₂-types, as well as Ni₂In-type domains; thus a continuous transition from the CdI₂ to Ni₂In type is confirmed, to the best of our knowledge, for the first time. Lattice parameter variations and the transition CdI₂–NiAs–Ni₂In in the ternary phase field were analysed.
Furthermore, vertical sections at 10, 40, 55, 60 and 70 at.% Ni were determined. A liquidus surface projection and a reaction scheme of the system were constructed as well. Altogether, 17 invariant phase reactions, including 3 eutectic reactions, 2 peritectic reactions, 11 transition reactions and one maximum were discovered.
Coupled In/Te and Ni/vacancy ordering and the modulated crystal structure of a B8 type, Ni<inf>3±x</inf>In<inf>1-y</inf>Te <inf>2+y</inf> solid solution phase
2007, Journal of Solid State Chemistry
The commensurate superstructures of a NiAs/Ni₂In type parent structure, Ni_3.32InTe₂ and Ni_3.12In_0.86Te_2.14 (q=γ[0 0 1]^*, γ=2/3) as well as one dimensionally incommensurate structure of Ni₃InTe₂ (γ=0.71) were refined from neutron powder diffraction data (R_wp=4.77%, 4.53% and 4.91% for the three structures, respectively, at 298 K). The commensurate structures were refined in the P6₃/mmc space group (c=3c_NiAs). The stacking sequence at the hcp array is -In/Te/Te/- and the trigonal bipyramidal site within the In layer, Ni(2), is partially occupied while it is empty in the Te layers. The octahedral position in between the In and Te layers, Ni(1a), is fully occupied while the octahedral position in between two adjacent Te layers, Ni(1b), is partially occupied. With decreasing In and Ni content, the modulation wave vector, γ, was found to increase continuously until γ=1. From this, crenel functions to describe the whole homogeneity range of the solid solution were constructed with the length of the atomic domains Δ^Te=γ (and hence Δ^In=Δ^Ni=1−γ) and Δ^Ni(1b)=γ/2 (and hence Δ^Ni(1a)=1−γ/2) which were then used for the refinement of the incommensurate structure of Ni₃InTe₂. The corresponding effect in real space is that the single In layers separating double layers of Te occur less frequent when γ in increasing until at γ=1 the CdI₂ type structure of Ni₁₊_xTe₂ is reached.

View all citing articles on Scopus

¹: To whom correspondence should be addressed. E-mail: [email protected].

View full text

Regular ArticleAn Electron and X-Ray Diffraction Investigation of Ni1+xTe2 and Ni1+xSe2CdI2/NiAs Type Solid Solution Phases

Abstract

J. Solid State Chem.

J. Solid State Chem.

J. Solid State Chem.

J. Solid State Chem.

J. Solid State Chem.

J. Solid State Chem.

J. Solid State Chem.

J. Crystal Growth

J. Solid State Chem.

J. Solid State Chem.

Regular Article
An Electron and X-Ray Diffraction Investigation of Ni_1+xTe₂ and Ni_1+xSe₂CdI₂/NiAs Type Solid Solution Phases