The Structure and Orientation of DMSO Molecules in the Interlayer of Montmorillonite

The structure and orientation of DMSO molecules in the interlayer of montmorillonite was investigated by FTIR and XRD. The adsorbed DMSO molecules were separated into physisorption and chemisorption. The former corresponded to 1.892 nm phase on 001 plane. DMSO molecules were adsorbed on the sheet of Si-O through the rhombus-cone plane of C.C. and S, oxygen atom hung in the interlayer space, and formed hydration bonding with water molecules. The later was for adsorbed DMSO molecules which directly coordinated to Mg²⁺ ion through oxygen atom. Sulphur atom at the rhombus-cone vertex interreacted with the sheet of Si-O, in this case, d₀₀₁ was 1.8423 nm.