丙酮酸稀土化合物的红外光谱研究

本文研究了 Y、La、Ce、Pr、Nd、Sm、Eu、Gd、Dy、Ho 十种丙酮酸稀土化合物的 FT-IR 光谱,对400-2000cm~(-1)的主要红外吸收谱峰进行了归属.400-200cm~(-1)有三个随稀土原子序数递增峰位向高频率位移的谱带,指认为M-O 伸缩振动吸收峰。它们的红外光谱表明,丙酮酸以酸根形式采用螯合桥式三齿方式配位,并且某些谱峰有裂分或拓宽现象。配位键以离子键成分为主。

STUDIES ON THE INFRARED SPECTRA OF SOME RARE EARTH COMPOUNDS WITH PYRUVIC ACID

FT-IR spectra of La,Ce,Pr,Nd,Sm,Eu,Gd,Dy,Ho,Y compound with pyruvic acid have been studied.The principal infrared absorption bands have been assigned for the region 400-2000cm~(-1).Three IR bands in the region 200-400cm~(-1)are shifted obviously to higher fre- quency with the increasing of the atomic number of rare earth ion,these were belived to be M-O bond stretching mode absorptions.The IR spectra also indicated that the carboxylate groups have the form of chelation bridging tridentate to rare earth ions,ie.one of the carboxyl oxygens was shared between two adjacent metal ions,moreover,the spltting and broad bands are existed in IR spcctra of the compounds.The experimental results showed that the M-O bond of these compounds is principally ionic.