Quantitative determination of antiphase boundary profiles in long period superstructures. I : real space analysis

Abstract

Long period structures have been thus extensively studied since about forty years with two main preoccupations ; I) to find a general microscopic description of the structures, it) to explain the origin of their stability and of their structural properties. Pioneering studies used X-ray diffraction and electron diffraction. On this basis, two kinds of structure models have been proposed. In the first one, Fujiwara [7] describes the structure assuming sharp domain walls strictly contained in cube planes whereas the second model proposed by J6hanno and P£rio [8] takes into account wavy antiphase boundaries.

Antiphase phenomena in 2d ising square lattice

“…Amongst two dimensional faults in solids, we can quote the Antiphase Boundaries (APBs) to which many works have been devoted. From the analysis of previous works [1][2][3][4][5] we can conclude that the influence of APBs on the properties (magnetic, mechanical…) of the materials depends strongly on the density of APBs [6] and on the temperature. In Sr 2 FeMoO 6, magnetization measurements revealed a slightly lowered saturation magnetization for the sample exhibiting the highest concentration of APBs as compared to samples with low concentration of APB atoms [5].…”

“…Here, i and j refer to the spin coordinates respectively in x-and y-directions. The generated lattice has the size (L+2) 2 , and the spins of the following groups of spins are pointed in the same direction: (…”

X-Ray, Electron Diffraction and HREM studies of KHTi4O9, xH2O Thermolysis: Characterization of K4Ti16O34

“…Acid-exchange of the potassium parent was [5,16]. [6][7][8][9]. In this approach, a basic structure is considered as modulated, i. e. divided into "modules" by a set of planar interfaces separated by a constant spacing A.…”

Quantitative analysis of periodic antiphase boundaries by lattice image simulations

“…The advantage of using electrons is the obtention of images as well as diffraction patterns which is not possible with the other techniques. In particular, the analysis of high resolution images can lead to the experimental determination of the modulation function which describes the variation of the order parameter across the boundaries [5,6,7,8]. When the profiles determined from the different techniques are compared, it appears that *New address: CEA/Ddpartement de Recherche Fondamentale sur la Mati~re Condens~/SP2M/S, 17 Rue des Martyrs, 38054 Grenoble Cedex 09, France.…”

“…The profiles deduced from these simulated images are compared to the input data. The copper palladium has been chosen mainly because well defined LPS exist in this system and because experimental data are available to make direct comparison between the different techniques [7,8,9].…”