Hamiltonian graph representation of zeolite frameworks and Si, Al ordering in the framework

摘要

In the first part, a topological characterization of various zeolite frameworks is performed on the basis of the Hamiltonian graph. It affords a simple representation of the framework connectivity, and presents some possibility of the classification as well as the prediction of unknown frameworks. In the second part, a simple and direct method based on the connectivity matrix is presented, by which all the possible Al distributions in a given framework are derived exhaustively under the restriction of Loewenstein's rule. An example of Al preference site determination is applied for zeolite ZSM-5 and compared with the result by the SCF-MO method.