结构铁的还原对绿脱石红外光谱的影响

伴随Fe^2 浓度增加和还原反应的进行，绿脱石红外光谱中位于3570，1030和821cm^-1吸收峰向低波数位移，其相应的振动方式分别为0-H伸缩振动、Si-Ob（基部氧）面内振动和FeO-H变形的振动，还原反应对Si-Oa（顶部氧）相互作用在1110cm^-1处产生的扇峰没有影响。结构铁的还原导致848cm^-1的吸收峰向较高能量方向转移，但在结构羟基完全重氢化后，Fe-OH振动在840cm^-1产生的吸收峰仍然保持不变，由于四面体和八面体薄层中间的压力减弱，Si-Ob振动能量随还原反应而降低。

Effect of Structural Iron Reduction on Infrared Spectra of Nontronite

As the Fe 2+ content increases upon reduction, infrared spectra of nontronite indicate shifts to lower wave number in peaks located at 3 570, 1 030, and 821 cm -1 , which are assigned to vibrational modes for O-H stretching, Si-O b(basal oxygen) tetrahedral vibrations, and FeO-H deformation, respectively. A shoulder at 1110cm -1 resulting from Si-O a(apical oxygens) interactions appears to be unchanged with reduction. The absorption band at 848 cm -1 shifts to higher energy with reduction of structural iron, and persists at 840 cm -1 which is assigned to a Fe-OH mode after complete deuteration of structural hydroxyls. Due to a decrease in stress forces between the tetrahedral and octahedral sheets, the Si-O b mode shifts to lower vibrational energy with reduction.