Interaction of CO molecule with Au/MOR catalyst: ONIOM-PM6 study, active sites, thermodynamic and vibrational frequencies.
ONIOM calculations have been carried out to determine geometries, adsorption energies, and vibrational frequencies of CO on a model for Au-exchanged mordenite catalysts, Au/MOR. The CO-calculated vibrational frequencies (upsilon(CO)) are in good agreement with the reported experimental values. We proposed to interpret the frequency results. CH(3)COCH(3) and CH(3)SH adsorption enthalpy calculations on Au/MOR model show that the Au/MOR catalyst behaves like a soft acid according to Pearson's rule. A higher structural deformation degree of the mordenite was found in the calculations with PM6 than with universal force field approach approach. A new pseudopotential (ACEP-121) was developed to improve the Au-Au distance, and Au ionization potential.
Laboratorio de Química Computacional, Centro de Química, Instituto Venezolano de Investigaciones Científicas, Apartado 21827, Caracas 1020-A, Venezuela. asierral@ivic.gob.ve
Anibal
A
Sierraalta
Rafael
R
Añez
Lenin
L
Diaz
Roberto
R
Gomperts