Mn_5(PO_3(OH))_2(PO_4)_2(H_2O)_4的水热合成和光谱研究  

Hydrothermal Synthesis and Spectra Properties of Compound Mn_5(PO_3(OH))_2(PO_4)_2(H_2O)_4

作　　者：吴小园[1] 张汉辉[1] 黄长沧[1] 孙瑞卿[1] 杨齐瑜[1] 林志华[1] 

机构地区：[1]福州大学化学系,福建福州350002

出　　处：《光谱学与光谱分析》2004年第6期694-697,共4页Spectroscopy and Spectral Analysis

基　　金：福建省自然科学基金 (E0 1 1 0 0 1 3);福建省科技三项基金(K0 2 0 2 8);结构化学国家重点实验室基金资助项目

摘　　要：在水热反应条件下合成出具有红磷锰矿结构的Mn5(PO3(OH) ) 2 (PO4 ) 2 (H2 O) 4单晶 ,在X ray单晶结构分析的基础上 ,对其固体紫外可见漫反射光谱、红外光谱、荧光光谱和热重光谱进行了研究。结果表明 ,构成该化合物的PO4 四面体及MnO6 八面体通过共顶点或共棱方式相连接 ,与P ,Mn配位的氧分为 3类 :即端基氧 (Od)、二桥氧 (Ob)和三桥氧 (Oc)。因而在 2 10和 2 5 0nm左右出现了Od→Mn和Ob ,c→Mn的荷移跃迁吸收谱带 ;在 10 0 0～ 110 0cm- 1 处 ,P—O的伸缩振动峰分裂为 3个 ;70 0～ 980cm- 1 处存在 3类Mn—O的伸缩振动。对标题化合物分别采用 2 18和 310nm的光激发 ,分别在 35 4和 4 13nm产生强而尖锐的荧光光谱发射峰 ,表现了很强的光学效应。热重分析表明该化合物在 2 70℃以下结构保持稳定 ,在 2 70～36 0℃范围内失去配位水。量化计算得单点能为 - 4 5 5 8 6 5 95 5 5 1a u ;前线轨道能量HOMO(Alpha) =- 0 2 80 80a u ,LOMO(Alpha) =0 0 15 2 7a u ,能隙为 0 2 96 0 7a u ;HOMO(Beta) =- 0 2 5 919a u ,LOMO(Beta)=0 0 0 10 8a u ,能隙为 0 2 6 0 72a u ;偶极矩为 4 2 0 82Debye。The title compound Mn-5 (PO3 (OH))(2) (PO4)(2) (H2O)(4) was synthesized under hydrothermal condition. Its crystal structure was determined by single-aystal X-ray diffraction. DRS, IR, fluorescence and TGA spectra were used to characterize the title compound. As a result, the compound is formed by linking with PO4 and MnO6, and the oxygen in it can be divided to three categories, so in IR spectra the characteristic peaks of Mn-O and P-O are separated in to three, respectively. In DRS there are two peaks at 210 and 250 nm coresponding O-d-->Mn and O-b,O-c-->Mn. In fluorescence spectra the emission peaks are located at 354 and 413 nm when excited at 218 and 310 nm. Besides, thermal behavior of the compound is discussed by TGA diagrams. Finally, quantum chemistry calculation is performed to explain the structure characteristic. HF = - 4 558.659 555 1 a. u, HOMO(Alpha) = - 0.280 80a. u, LOMO(Alpha) = 0. 015 27a. u, DeltaE((Alpha)) = 0. 296 07 a. u; HOMO(Beta) 0.259 19 a. u, LOMO(Beta) = 0. 00108 a. u, DeltaE((Beta)) = 0. 260 72 a. u and Dipole = 4.208 2 Debye.

关 键 词：红磷锰矿 防腐剂 水热合成 光谱分析 结构 量化化学 

分 类 号：P578.92[天文地球—矿物学] P575.4[天文地球—地质学]