A. A. Kubasov, L. Ye. Kitayev, S. V. Malyshev, Yu. V. Novakovskaya
The
quantum-chemical estimation of the effect of phosphorus atoms on the electron
acceptor properties of aluminum- and boron-containing zeolite clusters
Abstract
The effect of phosphorus atom introduced in a zeolite
cluster involving 10 silicon and aluminum atoms on the state of active
catalytic structure sites is estimated. Zeolite clusters modified with boron
are also considered. Electron density redistribution upon the zeolite
modification with boron and phosphorus, as well as upon the coordination of
probe water and ammonia molecules to the clusters is analyzed. Bond energies of
water or ammonia molecules coordinated to and acceptor sites of
phosphorus-containing zeolites are estimated. Experimentally discovered changes
in the acidic properties of zeolites resulting from accompanying their
modification with boron and phosphorus are interpreted.
Copyright (C) Chemistry Dept., Moscow State University, 2002
|
|