Neutron diffraction determination of full structures of anhydrous LiX and LiY zeolites

Abstract

Virtually monoionic LiX and LiY zeolites have been prepared by LiOH titration of parent NH 4 zeolites. Structural studies have been performed at room temperature on the anhydrous zeolites, Li 80.7 H 4.9Na 0.4Al 86Si 106O 384 and Li 46.0H 5.8Na 5.1K 0.1Al 57Si 135O 384, by powder neutron diffraction profile refinement in order to locate Li + cations. The cell parameters are 24.6716(10) and 24.4498(12) Å for LiX and LiY, respectively. Three positions have been found for Li +, sites I′ and II in the six-ring windows of the sodalite unit and site III′ in the supercage for the additional Li + of LiX.