Hyperfine interactions between unpaired electrons and framework atoms in aluminosilicate sodalites containing paramagnetic Na43+ clusters: a 29Si and 27Al MAS NMR study
Abstract
First NMR evidence is presented for hyperfine interactions between unpaired electrons and the framework atoms in alkali-metal doped zeolites by the 27Al and 29Si MAS NMR spectra of aluminosilicate sodalites loaded with paramagnetic Na43+ cluster which show up to seven resonances with characteristic down-field shifts caused by Fermi contact interactions between the unpaired electrons of sodium clusters and the Al and Si atoms of the sodalite framework.