New scheelite-type Cd_1∿x⌿span style='font-style: italic'>_xGd_2x(MoO₄)_1∿x(WO₄)_3x ceramics - their structure, thermal and magnetic properties

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• 作者：Elżbieta Tomaszewicz^a ; ^{tomela@zut.edu.pl" class="auth_mail" title="E-mail the corresponding author} ; Grażyna Dąbrowska^a ; Elżbieta Filipek^a ; Hubert Fuks^b ; ^{fux@zut.edu.pl" class="auth_mail" title="E-mail the corresponding author} ; Janusz Typek^b
• 关键词：A. Powders ; solid state reaction ; C ; Magnetic properties ; C ; Thermal properties ; CdMoO4&ndash ; Gd2(WO4)3 system
• 刊名：Ceramics International
• 出版年：2016
• 出版时间：1 May 2016
• 年：2016
• 卷：42
• 期：6
• 页码：6673-6681
• 全文大小：2066 K

文摘

Polycrystalline samples of scheelite-type Cd_1−3x⌷_xGd_2x(MoO₄)_1−3x(WO₄)_3x solid solution with limited homogeneity (0<x≤0.25) and cationic vacancies (denoted as ⌷) have successfully prepared by a high-temperature annealing of CdMoO₄/Gd₂(WO₄)₃ mixtures composed of 50.00 mol% and less of gadolinium tungstate. Initial reactants and obtained ceramic materials were characterized by XRD, simultaneous DTA–TG, and SEM techniques. A phase diagram of the pseudobinary CdMoO₄–Gd₂(WO₄)₃ system was constructed. The eutectic point corresponds to 1404±5 K and ~70.00 mol% of gadolinium tungstate in an initial CdMoO₄/Gd₂(WO₄)₃ mixture. With decreasing of Gd³⁺ content in a CdMoO₄ framework, the melting point of Cd_1−3x⌷_xGd_2x(MoO₄)_1−3x(WO₄)_3x increases from 1406 (x=0.25) to 1419 K (x=0.0833), and next decreases to 1408 K (x=0). EPR method was used to identify paramagnetic Gd³⁺ centers in Cd_1−3x⌷_xGd_2x(MoO₄)_1−3x(WO₄)_3x for different values of x parameter as well as to select biphasic samples containing both Cd_0.25⌷_0.25Gd_0.50(MoO₄)_0.25(WO₄)_0.75 and Gd₂(WO₄)₃.