RE:KYb(WO4)2(RE=Nd3+,Er3+)激光晶体生长与结构特性

采用泡生法(Kyropoulos method)生长了稀土掺杂钨酸镱钾[RE:KYb(WO4)2,RE=Nd3+,Er3+]激光晶体,并对其结构特性进行了研究。RE:KYb(WO4)2晶体是由WO6,REO8和KO123种基团组成,W2O10二聚体通过WOW单氧桥相连,在平行于c轴方向上形成(W2O8)n多重带。REO8和KO12多面体共顶相连,沿[101]和[110]方向形成了具有二维层结构的延长带。X射线粉末衍射分析表明:Nd3+:KYb(WO4)2和Er3+:KYb(WO4)2两种晶体具有低温β相RE:KYb(WO4)2结构,属于单斜晶系,空间群为C2/c,计算了晶格常数。晶体红外光谱测试结果表明:在630～930cm-1范围存在5个较强的红外吸收峰,这些吸收峰是由WO4基团的伸缩振动引起的。最后,对峰值与相应的振动模式进行了归属,证实了晶体中WOOW双氧桥和WOW单氧桥键的存在。

GROWTH AND STRUCTURE CHARACTERISTICS OF RE(Nd3+,Er3+)-DOPED POTASSIUM YTTERBIUM TUNGSTATE LASER CRYSTAL

RE:KYb(WO4)2 (RE=Nd3+,Er3+) crystals were grown by the Kyropoulos method,and their structural characteristic was investigated.The structure of the crystals is composed of three kinds of groups,including WO6,REO8 and KO12 polyhedrons.The W2O10 dimmers are connected by WOW single oxygen bridging bonds and form (W2O8)n bands along c axis in parallel direction.The REO8 and KO12 polyhedrons in the crastals are joined by common vertex and form an elongated band with the structure of two-dimensional layer along [101]and [110]directions.Then powder X-ray diffraction analysis indicates that the two crystals of Nd3+:KVb(WO4)2 and Er3+:KYb(WO4)2 belong to a monoclinic system with a space group C2/c.which indicates that the crystals obmined are β-RE:KYb(WO4)2.The cell parameters of the two crystals were calculated,too.The infrared spectra show that they have five strong infrared absorption peaks from 630 to 930 cm-1,which woro caused by stretching vibration of WO4 groups.Finally,the vibration modes and frequencies were identified,which confirmed the existence of WOOW double oxygen bridge and WOW single oxygen bridge bonds in the crystals.