不同地域天然伊利石的多光谱表征与比较

多种现代光谱技术的应用为不同地域天然伊利石光谱信号的匹配提供一致的、互为补充的证据，以解决使用单一技术经常遇到的不确定性问题．在固态^29Si和^27Al魔角自旋核磁共振光谱中分别出现多重Q^3mAl结构单元和四配位Al形态的共振信号，表明硅氧四面体层面中存在不同程度的同晶置换以及四面体点位上硅、铝分布的无序性，进而导致表面反应位的异质性．特征化X射线衍射峰显示样品结构中存在不同组份层面混杂的现象．相应的红外、喇曼光谱以及^29Si共振信号表明，其中两个样品含有较多的石英杂质，但对伊利石表面酸碱行为的影响并不显．

Characterization and Comparison of Natural mites from Different Origins by Multiple Spectroscopic Methods

The combined spectroscopic techniques provided consis te nt and complementary evidence for verifying the assignment of spectral signals, and resolving some ambiguities, which were usually encountered when using a sing le method. The presence of multiple Q 3 mAl structural units and fourfold co ordinated Al species in 29 Si and 27 Al MAS NMR spectra of the natural illites, indicated different extents of isomorphic substitution of Si by Al in the siloxane tetrahedral sheets and a disordered distribution of Si/Al at the te trahedral sites. This case possibly led to heterogeneous surface sites. In addit ion, the characteristic diffraction lines in the XRD profiles showed mixed compo nent layers in the layer structure of illites. Quartz impurity in two samples wa s indicated by the corresponding IR and Raman vibrations as well as by the 2 9 Si resonance. However, the influence of quartz impurity on the surface acid- base behavior of the natural illites was not so significant.