Phase Transitions in Two-Dimensional Monolayer Films on the (100) Face Centered Cubic Crystal Surface†

The influence of the type of crystal structure of complex gadolinium oxides on their catalytic activity was studied using a wide range of physicochemical methods. It was shown that the synthesized nanocrystalline powders Gd2Zr2O7 form highly symmetric face-centered cubic crystal structures. In the course of catalytic experiments, it was found that the formation of a cubic structure increases the degree of conversion of propane and the shift of cracking temperatures to a lower area. The formation of various defects contributes to the course of the dehydrogenation or degradation reaction due to the different number of catalytic centers.

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On the Dynamical Propeties of a Strongly Anharmonic Face-Centered Cubic Crystal

International Journal of Modern Physics B ◽

10.1142/s021797929800168x ◽

1998 ◽

Vol 12 (27n28) ◽

pp. 2869-2879 ◽

Cited By ~ 2

Author(s):

V. I. Zubov ◽

C. G. Rodrigues ◽

M. F. Pascual

Keyword(s):

Crystallographic Direction ◽

Face Centered Cubic ◽

Mean Square ◽

Cubic Crystal ◽

Cubic Lattice ◽

Consistent Field ◽

Self Consistent ◽

Self Consistent Field ◽

Face Centered ◽

Anharmonic Crystals

We study the interatomic correlations and mean square relative displacements (MSRD) in anharmonic crystals on the basis of the correlative method of unsymmetrized self-consistent field (CUSF). Here we present general formulae for crystals with the anharmonicity, including the strong one, up to the fourth anharmonic terms and perform calculations of the quadratic correlation moments (QCM) in a crystal with face centered cubic lattice, namely in solid Ar. The second order of CUSF allows one to investigate correlations in this lattice between the nearest, second, third and fourth neighbors. The anharmonicity was demonstrated to have strong effect on the interatomic correlations at temperatures above 0.4 of the melting temperature causing a drastic rise near the spinodal point. The dependence of QCM on the distance between atoms and on the crystallographic direction is discussed.

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The diffusivity, mobility, and correlation factor for solute vacancy diffusion in an edge dislocation in a face‐centered‐cubic crystal

Journal of Applied Physics ◽

10.1063/1.339354 ◽

1987 ◽

Vol 62 (7) ◽

pp. 3077-3079 ◽

Cited By ~ 3

Author(s):

J. P. Stark

Keyword(s):

Edge Dislocation ◽

Correlation Factor ◽

Face Centered Cubic ◽

Vacancy Diffusion ◽

Cubic Crystal ◽

Face Centered

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Upconversion Luminescence Properties of Er3+ Doped Yb2Ti2O7 Nanophosphor by Gd3+ Codoping

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11833 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3690-3694 ◽

Cited By ~ 6

Author(s):

B. S Cao ◽

J. L Wu ◽

X. H Wang ◽

Z. Q Feng ◽

B Dong

Keyword(s):

Cell Parameter ◽

Upconversion Luminescence ◽

Sol Gel ◽

Nominal Composition ◽

Face Centered Cubic ◽

Cubic Crystal ◽

Crystal Field Symmetry ◽

Field Symmetry ◽

Face Centered ◽

Upconversion Emissions

Er3+ doped Yb2Ti2O7 nanophosphors by Gd3+ codoping with nominal composition of (Er0.05Yb0.95−xGdx)2Ti2O7 (x = 0, 0.2, 0.4, 0.6, 0.8, and 0.95) have been prepared by sol–gel method. −Er3+–Gd3+ codoped Yb2Ti2O7 was characteristic of a typical face-centered cubic crystal phase, and the unit cell parameter increased linearly with the increase of Gd3+ concentration. Under a 976 nm laser diode excitation, both green and red upconversion emissions were observed and the upconversion emissions were enhanced significantly by Gd3+ codoping, showing the strongest green and red emissions at 80 mol% Gd3+ codoping. The intensity ratio of green to red emissions (Igreen/Ired) increased monotonously with the increase of Gd3+ concentration. The energy transfer between Yb3+ and Er3+ and the variation of local crystal field symmetry of Er3+ by the substitution of Yb3+ by Gd3+ ions led to the improvement of upconversion properties of Er3+–Gd3+ codoped Yb2Ti2O7 nanophosphors.

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