29Si MAS NMR study of a highly siliceous EUO-type material

Abstract

The ²⁹Si MAS NMR spectrum of a highly crystalline and siliceous (Si/Al = 1482) sample of an EUO-type material contains at least 13 peaks. In the published topology EUO has only 10 crystallographic sites. Thus, the symmetry of the material is lower than that of the topology. The most likely space group of this sample is Cm2b, Cmm2, Pmab or Pmma. Increasing the temperature of the sample from room temperature to 100 °C does not produce a phase change, in contrast to silicalite-1.