Pentasil-zeolites are defined by their structure type, and more specifically by their X-ray diffraction patterns.
As early as 1967, Argauer and Landolt worked out parameters for the synthesis of pentasilzeolites, particularly those relating to the following molar ratios: OH−/SiO2 = 0.07-10, SiO2/Al2O3 = 5-100, H2O/SiO2 = 1-240 [REF].