Cation location in dehydrated zeolite NaY revisited: SI position is displaced from the center of the hexagonal prism

Abstract

Recent multiquantum magic-angle spinning and double rotation 23Na-NMR experiments of dehydrated zeolite NaY have shown that sodium cations on site SI in the hexagonal prism are subject to appreciable quadrupolar interactions. This indicates that the SI cations are not located in the classical center position derived from X-ray and neutron diffraction studies but are displaced from the center by 0.6 Å along the [111] direction.