Affiliations: Labs. Química Computacional y Fisicoquímica de Superficies, Centro de Química, Caracas, Venezuela | [x] Centro Tecnológico, Instituto Venezolano de Investigaciones Científicas, IVIC, Caracas, Venezuela | [y] Departamento de Química, Facultad Experimental de Ciencias, La Universidad del Zulia LUZ, Maracaibo, Venezuela | [z] Centro de Química, Instituto Venezolano de Investigaciones Científicas, IVIC, Caracas, Venezuela
Correspondence:
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Corresponding author: Beulah Griffe, Labs. Química Computacional y Fisicoquímica de Superficies, Centro de Química, IVIC, Apdo Postal 20632 Caracas 1020-A, Venezuela. E-mail: [email protected].
Abstract: Quantum chemistry calculations were done, using the ONIOM2 methodology at two different levels of calculation, B3LYP for the high level and UFF for the low level. These calculations were performed on Au3/SAPO-11, Au4/SAPO-11, CO-Au3/SAPO-11 and CO-Au4/SAPO-11 aggregates to analyze the geometries of small clusters of Au3 and Au4 on SAPO-11 support. Au3 cluster present a triangle structure in Au3/SAPO-11. Au4 cluster shows a “Y shaped” structure in Au4/SAPO-11. Au4 as a rhombus structure is also studied but it is an unstable intermediate to the “Y shaped” structure. The CO interaction with Au3 and Au4/SAPO-11 is studied, this CO adsorption is different from reported in the literature. The formation energy ΔEF of the aggregates and the CO adsorption energy ΔEads on them are presented.
