溴氢氧化镧的合成及结构

SYNTHESIS AND CRYSTAL STRUCTURE OF LANTHANUM HYDROXIDE BROMIDE

在常温常压下由溴氧化镧与水蒸汽反应合成了溴氢氧化镧,用示差热分析和热失重分析方法研究了溴氢氧化镧的热分解过程——在空气中于360—405℃,在氮气流中于315—347℃热分解,脱水后生成溴氧化镧。用粉末X射线衍射确定了本实验所合成的溴氢氧化镧(La(OH)_(2)Br)的晶体结构,是斜方晶系,α=8.9064,6=13.024,c=5.5630。讨论了溴氢氧化镧的有关化学性质。

The lanthanum hydroxide bromide,La(OH)2Br,has been synthesised by the reaction of lanthanum oxybromide with water vapor under ordinary temperature and pressure.LaOBr+H_(2)O(vapor)=La(OH)2BrThe thermal decomposition process and crystal structure of the La(OH)2Br have been investigated by using D.T.A.,T.G.A.and X-ray diffraction methods.The La(OH)2Br decomposes thermally at 360-405°C in air and at 315-347°C under nitrogen stream to form lanthanum oxybromide and water.La(OH)_(2)Br=LaOBr+H_(2)O|The X-ray diffraction data of the La(OH)_(2)Br have been indexed on a orthorhombic system.The refined^lattice parameters are a=8.9064A,b=13.024A,c=5.5630A.Some chemical properties of the La(OH)_(2)Br are discussed.