Location and movement on dehydration of Cu2+ in Cs7Na5A zeolite from electron spin echo modulation analysis

Abstract

It is shown that paramagnetic ions like Cu2+ can be located and that their motion upon dehydration in zeolites can be monitored by electron spin echo modulation analysis. In Cs7Na5A zeolite, Cu2+ is located inside the β cage about 0.1 nm below a hexagonal window between the β and α cages. The Cu2+ is coordinated to three lattice oxygens and one water molecule. On dehydration Cu2+ moves out of the β cage along the threefold axis of the hexagonal window to about 0.1 nm above the hexagonal window into the α cage.