TY - JOUR
T1 - Crystal structures of (Ba1-xLax)[Mg(1+x)/3Nb(2-x)/3]O 3 with 0.9 ≤ x ≤ 1.0
AU - Park, Hyun Min
AU - Lee, Hwack Joo
AU - Cho, Yang Koo
AU - Nahm, Sahn
N1 - Funding Information:
This work was financially supported by the Korean Ministry of Science and Technology (MOST) through the NRL program.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2003/4
Y1 - 2003/4
N2 - Based on a structure model of mixture of phases, the crystal structure analysis of (Ba1-xLax)[Mg(1+x)/3Nb(2-x)/3]O 3 (BLMN) (x = 0.9 and 1.0) by Rietveld refinements was carried out. The pure La(Mg2/3Nb1/3)O3 (LMN) and BLMN (x = 0.9) actually consist of a two-phase mixture rather a single phase. One is Fm-3̄m, which is cubic and 1:1 ordered and the other is P21/n, which is monoclinic and has both 1:1 ordering and the antiphase and inphase tilting of oxygen octahedra with a-a-c+. The weight fraction of the Fm-3̄m phase is 17.5% at x = 0.9 and further decreases to 7.5% in pure LMN. Meanwhile, that of the P21/n phase is 82.5% at x = 0.9 and further increases to 92.5% in pure LMN. The I4/m phase, which is present as a minor phase from x = 0.3 to 0.7, disappeared when x ≥ 0.9. The abrupt change of the x-ray diffraction pattern at x = 0.9 is caused by a change of major phase from Fm-3̄m to P21/n phase in the matrix.
AB - Based on a structure model of mixture of phases, the crystal structure analysis of (Ba1-xLax)[Mg(1+x)/3Nb(2-x)/3]O 3 (BLMN) (x = 0.9 and 1.0) by Rietveld refinements was carried out. The pure La(Mg2/3Nb1/3)O3 (LMN) and BLMN (x = 0.9) actually consist of a two-phase mixture rather a single phase. One is Fm-3̄m, which is cubic and 1:1 ordered and the other is P21/n, which is monoclinic and has both 1:1 ordering and the antiphase and inphase tilting of oxygen octahedra with a-a-c+. The weight fraction of the Fm-3̄m phase is 17.5% at x = 0.9 and further decreases to 7.5% in pure LMN. Meanwhile, that of the P21/n phase is 82.5% at x = 0.9 and further increases to 92.5% in pure LMN. The I4/m phase, which is present as a minor phase from x = 0.3 to 0.7, disappeared when x ≥ 0.9. The abrupt change of the x-ray diffraction pattern at x = 0.9 is caused by a change of major phase from Fm-3̄m to P21/n phase in the matrix.
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U2 - 10.1557/JMR.2003.0137
DO - 10.1557/JMR.2003.0137
M3 - Article
AN - SCOPUS:0038337807
VL - 18
SP - 1003
EP - 1010
JO - Journal of Materials Research
JF - Journal of Materials Research
SN - 0884-2914
IS - 4
ER -