Extra-large and intersecting pores Thermally stable zeolites with large pores, such as zeolite Y with 12-membered rings, are used for converting large molecules from petroleum into smaller, more useful hydrocarbons. Lin et al . report the synthesis of ZEO-1, a thermally stable zeolite with extra-large, 16-membered rings. The use of tricyclohexylmethylphosphonium as an organic structure–directing agent created a zeolite with a fully interconnected multidimensional framework and a very high specific surface area. —PDS