n-C_(16)H_(33)NH_3X和(n-C_(16)H_(33)NH_3)_2MX_4的红外光谱研究

INFRARED SPECTROSCOPIC STUDY OF n-C_(16)^-H_(33)NH_3X AND (n-C_(16)H_(33)NH_3)_2MX_4

在室温和液氮温度下研究了(n-C_(16)H_(33)NH_3)_2MX_4(简称C_(16)MX)及其相应化合物n-C_(16)H_(33)NH_3X(简称C_(16)X)于4000～50cm^(-1)范围的红外光谱。结果表明,它们都形成N-H…X型氢键,氢键强度是C_(16)X大于C_(16)MX。后者氢键的强度是按Cl>Br>I的顺序递减。C_(16)MX的光谱性质可按金属离子性质分为Cu^(2+)(Cu^(2+)、Cd^(2+)、Mn^(2+))和Zn^(2+)(Zn^(2+)、Co^(2+))两组,阴离子配位多面体的形状对其光谱性质有明显影响。还比较了室温与低温下的远红外光谱,证明了M—X键是离子键。

The infrared spectra of the perovskite compounds of general formula (n-C_(16)H_(33)NH_3)_2MX_4 (abbr. as C_(16)MX; M=Cu^(2+), Cd^(2+), Mn^(2+), Zn^(2+) or Co^(2+); X=Cl, Br or I) and their corresponding compounds n-C_(16)H_(33)NH_3X (abbr. as C_(16)X) have been studied in the 4000～50cm^(-1) range at room and liquid nitrogen temperature. The results showthat the hydrogen bonds are stronger in C_(16)X than in C_(16)MX and the strength of hydrogen bonds decrease in Cl>Br>I order for C_(16)MX. The characteristic of the spectra of C_(16)MX can be grouped under two heads—Cu^(2+) group (Cu^(2+), Cd^(2+), Mn^(2+)) and Zn^(2+) group (Zn^(2+), Co^(2+)) by means of the two different polyhedrons of anions. The comparison between the far infrared spectra at the two temperatures suggests that the M—X bonds are ionic.