Vibrational Analysis of 3‐Glycidoxypropyltrimethoxysilane Polymer

Summary In this work 3-glycidoxypropyltrimethoxysilane polymer with inorganic SiOSi bonds was prepared by a sol-gel process. The structure of polymer was characterized by vibrational spectroscopy (Raman and IR). The interpretation of vibrational spectra is supported by the normal coordinate analysis based on density functional theory (DFT) calculations. A conformational and vibrational analysis of lowest energy dimer structure has been carried out by DFT calculations using Becke's three-parameter exchange functional in combination with the Lee-Young-Parr correlation functional (B3-LYP) and standard 6–311 + G(d,p) basis set. The comparison of theoretical spectra with the experimental data enabled us to extract the characteristic vibrational bands of polymer structure. The inorganic polymerization gives rise to siloxane network with SiOSi stretchings at 1030 and 1134 cm−1 suggesting the ladder-type structure of GPTMS polymer.