Syntheses, crystal structures, and thermal analyses of solvent-free Ca(AlD4)2 and CaAlD5
Syntheses, crystal structures, and thermal analyses of solvent-free Ca(AlD4)2 and CaAlD5
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DOI：
10.1016/j.jallcom.2009.07.164
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发表时间：
2009-11
影响因子：
6.2
通讯作者：
Toyoto Sato;M. Sørby;K. Ikeda;S. Sato;B. Hauback;S. Orimo
中科院分区：
文献类型：
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作者：
Toyoto Sato;M. Sørby;K. Ikeda;S. Sato;B. Hauback;S. Orimo
在氘气压力为0.3MPa的条件下，以CaD 2和AlD 3为原料，分别以1：2和1：1的摩尔比进行机械化学球磨，直接合成了无溶剂的Ca（AlD 4）2和CaAlD 5。采用高分辨同步辐射粉末X射线衍射（SR-PXD）、粉末中子衍射（PND）、拉曼光谱和热重分析（TG）对产物进行了表征。利用SR-PXD和PND数据对Ca（AlD_4）_2的晶体结构进行了测定和修正。它具有正交Ca（BF 4）2型结构，a=13.4491（27），B=9.5334（19），c=9.0203（20），空间群Pbca（No.61），Z=8。拉曼光谱显示了AlD 4四面体在480- 650 cm-1和1290- 1340 cm-1处的弯曲和拉伸模式。TG分析表明，Ca（AlD_4）_2释放了4.8wt.%氘气的起始温度为427 K。根据PND数据确定并精修了CaAlD 5的晶体结构，发现其为单斜α-SrAlF 5型结构，a=9.8000（19），B=6.9081（13），c=12.4503（23），β=137.936（4）°，空间群为P21/c（No.14），Z=8。CaAlD 5的拉曼光谱显示AlD 6八面体的弯曲和拉伸模式分别在725和1060- 1170 cm −1处。热重分析表明，CaAlD 5的释放量为7.1wt.%氘气的起始温度为554 K。
Solvent-free Ca(AlD4)2and CaAlD5were synthesized directly by mechanochemical milling of CaD2and AlD3in the molar ratios of 1:2 and 1:1, respectively, under deuterium gas pressure of 0.3MPa. The products were characterized by high-resolution synchrotron radiation powder X-ray diffraction (SR-PXD), powder neutron diffraction (PND), Raman spectroscopy, and thermogravimetry (TG) analysis. The crystal structure of Ca(AlD4)2was determined and refined with the SR-PXD and PND data. It takes an orthorhombic Ca(BF4)2-type structure with a=13.4491(27)Å, b=9.5334(19)Å, and c=9.0203(20)Å in the space group Pbca (No. 61) and Z=8. The Raman spectrum shows bending and stretching modes of the AlD4tetrahedron at 480–650cm−1and 1290–1340cm−1, respectively. TG analysis showed that Ca(AlD4)2releases 4.8wt.% of deuterium gas at the onset-temperature of 427K. The crystal structure of CaAlD5was determined and refined from the PND data and was found to be a monoclinic α-SrAlF5-type structure with a=9.8000(19)Å, b=6.9081(13)Å, c=12.4503(23)Å, and β=137.936(4)° in the space group P21/c (No. 14) and Z=8. The Raman spectrum of CaAlD5shows bending and stretching modes of the AlD6octahedron at 725 and 1060–1170cm−1, respectively. From TG analysis, CaAlD5releases 7.1wt.% of deuterium gas at the onset-temperature of 554K.