The comparison of the crystal structures of direnzoite, a new zeolite from Massif Central (France), and its synthetic counterpart ECR-1

The structures of the natural zeolite direnzoite and its synthetic counterpart ECR-1 were unravelled almost simultaneously using synchrotron powder diffraction. As a matter of fact, the structure refinement of Na-ECR-1 was crucial for the structure solution of direnzoite, which is the lastest discovered natural zeolite. The two structures are distinguished by a 1:1 polysomatic sequence of mordenite (MOR) and mazzite (MAZ) layers. Here, both the crystal structures are discussed and compared in the attempt to disclose their structure directing chemical and kinetic factors.