Synthesis, structural characterisation and magnetic properties of Gd14W4O33−xNy(0 ⩽ x ⩽ 17 ± 2, 0 ⩽ y ⩽ 9 ± 2), a new fluorite-related oxynitride
Synthesis, structural characterisation and magnetic properties of Gd14W4O33−xNy(0 ⩽ x ⩽ 17 ± 2, 0 ⩽ y ⩽ 9 ± 2), a new fluorite-related oxynitride
复制标题
新型萤石相关氮氧化物Gd14W4O33−xNy(0 ⩽ x ⩽ 17 ± 2, 0 ⩽ y ⩽ 9 ± 2)的合成、结构表征及磁性能
DOI：
10.1016/0925-8388(96)02325-0
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发表时间：
1996
影响因子：
6.2
通讯作者：
G. Svensson
中科院分区：
文献类型：
--
作者：
Mattias Nilsson;J. Grins;P. Käll;G. Svensson
在 700-1100 C 的温度范围内，制备了一系列 Gd:W 比值范围为 0.1-3.5 的结晶 Gd-W 氧化物，并用 NH{sub 3}(g) 流进行处理。除了先前报道的 GdWO{sub 3}N 和 Gd{sub 2}WO{sub 3}N{sub 2} 的形成之外，还获得了以下新结果： (i) 立方 Gd{sub 0.1}WO{sub 3} 氨解后形成（氧）氮化物 Gd{sub 0.1}W(O, N){sub x}，其 f.c.c.格子; (ii)前述Gd{sub 2}WO{sub 3}N{sub 2}表现出固溶度范围Gd{sub 3-x}W{sub 1+x}(O,N){sub y}，大约为0{<=}x{<=}1； (iii) Gd{sub 14}W{sub 4}O{sub 33}氨解产生氮氧化物，其组成随合成温度的变化而变化，根据Gd{sub 14}W{sub 4}O{sub 33-x}N{sub y}(0{<=}x{<=}17{+-}2, 0{<=}y{<=}9{+-}2)。所有强衍射线，包括纯氧化物 (x=y=0) 的衍射线，都可以用源自萤石的体心单斜晶胞来索引。对于 Gd{sub 14}W{sub 4}O{sub 33}，晶胞参数为 a=5.3592(11)、b=3.7295(7)、c=3.8636(8) A、{beta}=92.170(2) 和 V=77.17 A{sup 3}。然而，电子衍射图案中强烈的上部结构反射表明真正的晶胞要大得多。 Gd{sub 14}W{sub 4}O{sub 33-x}N{sub y}的部分结构测定已通过Rietveld方法进行。 15-300 K 温度区间内的磁化率测量显示 Gd{sub 14}W{sub 4}O{sub 33-x}N{sub y} 的居里-韦斯定律行为，其中每 Gd{sup 3+} 和 {theta}=-12.4{+-}1.1 K 的 {mu}{sub eff}=8.08{+-}0.06 个玻尔磁子组成。 （原件）
A series of crystalline Gd-W oxides, with Gd:W ratios spanning the values 0.1-3.5, has been prepared and treated with a flow of NH{sub 3}(g) in the temperature range 700-1100 C. Besides the previously reported formation of GdWO{sub 3}N and Gd{sub 2}WO{sub 3}N{sub 2}, the following new results were obtained: (i) cubic Gd{sub 0.1}WO{sub 3} upon ammonolysis forms an (oxy)nitride Gd{sub 0.1}W(O, N){sub x} with an f.c.c. lattice; (ii) the previously described Gd{sub 2}WO{sub 3}N{sub 2} exhibits a solid solubility range Gd{sub 3-x}W{sub 1+x}(O, N){sub y} with, approximately, 0{<=}x{<=}1; (iii) ammonolysis of Gd{sub 14}W{sub 4}O{sub 33} yields an oxynitride, the composition of which varies with the synthesis temperature according to Gd{sub 14}W{sub 4}O{sub 33-x}N{sub y}(0{<=}x{<=}17{+-}2, 0{<=}y{<=}9{+-}2). All strong diffraction lines, including those of the pure oxide (x=y=0), can be indexed with a body-centred monoclinic unit cell derived from that of fluorite. For Gd{sub 14}W{sub 4}O{sub 33} the cell parameters are a=5.3592(11), b=3.7295(7), c=3.8636(8) A, {beta}=92.170(2) and V=77.17 A{sup 3}. However, strong superstructure reflections in the electron diffraction patterns indicate that the true unit cell is considerably larger. A partial structure determination of Gd{sub 14}W{sub 4}O{sub 33-x}N{sub y} has been carried out by the Rietveld method. Magnetic susceptibility measurements in the temperature interval 15-300 K show a Curie-Weiss law behaviour for Gd{sub 14}W{sub 4}O{sub 33-x}N{sub y}, with {mu}{sub eff}=8.08{+-}0.06 Bohr magnetons per Gd{sup 3+} and {theta}=-12.4{+-}1.1 K for all compositions. (orig.)