Three new cadmium-selenium-oxyhalides, Cd₂(SeO₃)F_2, Cd₅(SeO₃)₄Cl₂(H₂O) and Cd₂(SeO₃)(OH)Br, were successfully synthesized by hydrothermal methods. Among these three compounds, Cd₅(SeO₃)₄Cl₂(H₂O) is noncentrosymmetric (NCS) and crystalizes in the polar space group P2₁. Powder second-harmonic generation (SHG) measurements using 1064 nm radiation indicate that Cd₅(SeO₃)₄Cl₂(H₂O) exhibits SHG intensity of about 0.6 times of KH₂PO₄ (KDP). Cd₂(SeO₃)F₂ and Cd₂(SeO₃)(OH)Br are centrosymmetric (CS) and crystalize in the space group Pnma and C2/c, respectively. The framework of Cd₅(SeO₃)₄Cl₂(H₂O) is constructed by interconnected cadmium-oxygen-chlorine layers and cadmium-oxygen-chlorine chains with Se ions embedded into by sharing three oxygen atoms. Cd₂(SeO₃)F₂ exhibits a three-dimensional (3D) structure with [CdO₃F₃] octahedra that are connected to [SeO₃] polyhedra. Cd₂(SeO₃)(OH)Br exhibits a 3D structure consisting of [Cd(1)O₂(OH)₂Br₂], [Cd(2)O₄(OH)Br] and [SeO₃] polyhedra. For all of the reported compounds, infrared spectroscopy, UV–vis diffuse reflectance spectroscopy and thermogravimetric measurements were performed.

通过水热法成功地合成了三种新的镉-硒卤氧化物Cd ₂（SeO ₃）F _2， Cd ₅（SeO ₃）₄ Cl ₂（H ₂ O）和Cd ₂（SeO ₃）（OH）Br。在这三种化合物中，Cd ₅（SeO ₃）₄ Cl ₂（H ₂ O）是非中心对称的（NCS），并在极性空间群P 2 _1中结晶。使用1064 nm辐射的粉末二次谐波生成（SHG）测量表明Cd ₅（SeO₃）₄ Cl ₂（H ₂ O）的SHG强度约为KH ₂ PO ₄（KDP）的0.6倍。Cd ₂（SeO ₃）F ₂和Cd ₂（SeO ₃）（OH）Br是中心对称的（CS），分别在空间群Pnma和C 2 / c中结晶。Cd ₅（SeO ₃）₄ Cl ₂（H ₂O）是由相互连接的镉-氧-氯层和镉-氧-氯链构成的，其中的Se离子通过共享三个氧原子嵌入其中。Cd ₂（SeO ₃）F ₂表现出具有[CdO ₃ F ₃ ]八面体的三维（3D）结构，该八面体连接到[SeO ₃ ]多面体。Cd ₂（SeO ₃）（OH）Br显示由[Cd（1）O ₂（OH）₂ Br ₂ ]，[Cd（2）O ₄（OH）Br]和[SeO ₃组成的3D结构]多面体。对于所有报告的化合物，均进行了红外光谱，紫外可见漫反射光谱和热重测量。