Study of the adsorption of organic molecules on transition metal exchanged zeolites via solid state NMR. Part 1: theoretical aspects.
A theoretical study is performed of the (1)H relaxation behavior of an organic molecule that is adsorbed in a zeolite exchanged with transition metal ions. An expression is derived for the spin-lattice and spin-spin relaxation rate constant of a uniform proton ensemble, while the occurrence of molecular exchange is taken into account. The influence is analyzed of an approach of a uniform proton ensemble toward the nearest neighboring paramagnetic ion system. It is shown that there exists a signal extinction effect, for which the critical distance was estimated.
Houthoofd
Kristof
K
Center for Surface Chemistry and Catalysis, Katholieke Universiteit Leuven, Kasteelpark Arenberg 23, 3001 Heverlee (Leuven), Belgium. Kristof.Houthoofd@biw.kuleuven.be
Grobet
Piet J
PJ
Jacobs
Pierre A
PA