Ordered B-Site Vacancies in an ABX3 Formate Perovskite

10.26434/chemrxiv.9746582.v1 ◽

2019 ◽

Author(s):

Hanna Boström ◽

Jonas Bruckmoser ◽

Andrew Goodwin

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Crystal Symmetry ◽

Nearest Neighbour ◽

Structural Characterisation ◽

Important Chemical ◽

Functional Implications ◽

New Type ◽

Metal Formate ◽

Site Vacancy

We report the synthesis and structural characterisation of a series of aliovalently doped metal–formate ABX3 perovskite frameworks [C(NH2)3]Mn2+1–x(Fe3+2x/3,Vx/3)(HCOO)3 (V = B-site vacancy). For sufficiently large x, the vacancies order, lowering the crystal symmetry from orthorhombic Pnna to monoclinic P2/n. This system establishes B-site vacancies as a new type of defect in formate perovskites, and one with important chemical, structural, and functional implications. Monte Carlo simulations driven by a nearest-neighbour vacancy repulsion model show checkerboard vacancy order to emerge for x > 0.6, in accord with experiment.

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Monte Carlo simulations of the two-dimensional quantal and classical spin systems — A new type of phase transition with vortices

Physics Letters A ◽

10.1016/0375-9601(77)90061-5 ◽

1977 ◽

Vol 60 (5) ◽

pp. 478-480 ◽

Cited By ~ 31

Author(s):

Masuo Suzuki ◽

Seiji Miyashita ◽

Akira Kuroda ◽

Chikao Kawabata

Keyword(s):

Phase Transition ◽

Monte Carlo ◽

Monte Carlo Simulations ◽

Spin Systems ◽

Two Dimensional ◽

Classical Spin ◽

New Type

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Data sets of migration barriers for atomistic Kinetic Monte Carlo simulations of Cu self-diffusion via first nearest neighbour atomic jumps

Data in Brief ◽

10.1016/j.dib.2018.01.066 ◽

2018 ◽

Vol 17 ◽

pp. 739-743 ◽

Cited By ~ 2

Author(s):

Ekaterina Baibuz ◽

Simon Vigonski ◽

Jyri Lahtinen ◽

Junlei Zhao ◽

Ville Jansson ◽

...

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Kinetic Monte Carlo ◽

Data Sets ◽

Nearest Neighbour ◽

Self Diffusion ◽

Migration Barriers ◽

Kinetic Monte Carlo Simulations

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Coil to rod transitions in Monte Carlo simulations of a short polyelectrolyte. III. Contact as a new type of bond

The Journal of Chemical Physics ◽

10.1063/1.459790 ◽

1991 ◽

Vol 94 (4) ◽

pp. 3213-3221 ◽

Cited By ~ 11

Author(s):

Chava Brender

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

New Type

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Interpretation of the spin glass behaviour of diluted magnetic semiconductors below the nearest-neighbour percolation threshold via realistic Monte Carlo simulations

Journal of Magnetism and Magnetic Materials ◽

10.1016/s0304-8853(00)00499-6 ◽

2000 ◽

Vol 221 (3) ◽

pp. 407-413 ◽

Cited By ~ 1

Author(s):

D. Karaoulanis ◽

J.P. Xanthakis ◽

N.C. Bacalis

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Percolation Threshold ◽

Spin Glass ◽

Diluted Magnetic Semiconductors ◽

Magnetic Semiconductors ◽

Nearest Neighbour ◽

Spin Glass Behaviour ◽

Diluted Magnetic

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Mechanism of “Order-Order” Kinetics in Ll2 Superstructure Studied by Computer Simulation

MRS Proceedings ◽

10.1557/proc-527-185 ◽

1998 ◽

Vol 527 ◽

Cited By ~ 3

Author(s):

P. Oramus ◽

R. Kozubski ◽

M.C. Cadeville ◽

V. Pierron-Bohnes ◽

W. Pfeiler

Keyword(s):

Monte Carlo ◽

Monte Carlo Simulations ◽

Saddle Point ◽

Narrow Range ◽

Pair Interaction ◽

Relaxation Processes ◽

Long Range Order ◽

Nearest Neighbour ◽

Interaction Energies ◽

Fast Relaxation

ABSTRACTMonte Carlo simulations of the isothermal long-range order (LRO) relaxation in A3B system with Ll2 superstructure have been performed within a model based on a vacancy jump mechanism between nearest neighbour lattice sites. The studies aimed at the explanation of the origin of two simultaneous LRO relaxation processes experimentally observed in Ni3Al. An effect of pair interaction energies and saddle-point energies (assigned to jumping atoms) was studied. The preference of vacancies for the A-sublattice (face centres), commonly postulated for Ni3Al, occurred only for a narrow range of pair-interaction energies within the domain corresponding to Ll2 ordering. It was found that the appearance of the fast relaxation process is definitely correlated with the efficiency of B-atom jumps, as well as with the values of the saddle-point energies. The results lead to a microscopic model of the “order-order” relaxation in Ll2 superstructure and yield new indications for the choice of pair-interaction energy parameters applied in Monte Carlo simulations of atomic migration in Ll2 intermetallic compounds.

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Low-voltage EDS of magnesium ferrite Dendrites in a FEG-SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100164854 ◽

1996 ◽

Vol 54 ◽

pp. 478-479

Author(s):

Matthew T. Johnson ◽

Ian M. Anderson ◽

Jim Bentley ◽

C. Barry Carter

Keyword(s):

Monte Carlo ◽

Quantitative Analysis ◽

Monte Carlo Simulations ◽

Cross Section ◽

Spatial Resolution ◽

Low Voltage ◽

Magnesium Ferrite ◽

X Ray ◽

Interaction Volume ◽

Ferrite Spinel

Energy-dispersive X-ray spectrometry (EDS) performed at low (≤ 5 kV) accelerating voltages in the SEM has the potential for providing quantitative microanalytical information with a spatial resolution of ∼100 nm. In the present work, EDS analyses were performed on magnesium ferrite spinel [(MgxFe1−x)Fe2O4] dendrites embedded in a MgO matrix, as shown in Fig. 1. spatial resolution of X-ray microanalysis at conventional accelerating voltages is insufficient for the quantitative analysis of these dendrites, which have widths of the order of a few hundred nanometers, without deconvolution of contributions from the MgO matrix. However, Monte Carlo simulations indicate that the interaction volume for MgFe2O4 is ∼150 nm at 3 kV accelerating voltage and therefore sufficient to analyze the dendrites without matrix contributions.Single-crystal {001}-oriented MgO was reacted with hematite (Fe2O3) powder for 6 h at 1450°C in air and furnace cooled. The specimen was then cleaved to expose a clean cross-section suitable for microanalysis.

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