The framework topology of ZSM-23: A high silica zeolite

ZSM-23, a high-silica zeolite, is orthorhombic, space group, Pmmn, with lattice parameters of: a = 5.01 ± 0.02Å, b = 21.52 ± 0.04Å, and c = 11.13 ± 0.03Å. The crystal structures of ZSM-22 and ZSM-23 are closely related in that both zeolites contain structurally identical subunits which generate noninterpenetrating, one-dimensional channels defined by 10-rings which are parallel to the short 5 Å axis. The 10-ring channel dimensions in ZSM-22 and ZSM-23 are essentially the same, though subtle differences exist in the shapes of the openings.