dThe concentrations of diisopropylnaphtalene (DIPN) isomers in experimental
equilibrium mixtures obtained on amorphous aluminosilicate and HY zeolite
have been measured by GC method. The total energy and Gibbs free energy of
the isomers were calculated by DFT method at the B3PW91/3-21G level. Compar
ison of the populations based on the DFT energies with the experimental con
centrations of DIPN isomers are in good agreement. This fact can suggest th
at isomerization is mainly determined by thermodynamic equilibrium. (C) 200
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