Electronic and geometric properties of ETS-10: QM/MM studies of cluster models

Anne Marie Zimmerman; Douglas J Doren; Raul F Lobo

doi:10.1021/jp0608877

Electronic and geometric properties of ETS-10: QM/MM studies of cluster models

J Phys Chem B. 2006 May 11;110(18):8959-64. doi: 10.1021/jp0608877.

Authors

Anne Marie Zimmerman¹, Douglas J Doren, Raul F Lobo

Affiliation

¹ Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.

PMID: 16671701
DOI: 10.1021/jp0608877

Abstract

Hybrid DFT/MM methods have been used to investigate the electronic and geometric properties of the microporous titanosilicate ETS-10. A comparison of finite length and periodic models demonstrates that band gap energies for ETS-10 can be well represented with relatively small cluster models. Optimization of finite clusters leads to different local geometries for bulk and end sites, where the local bulk TiO6 geometry is in good agreement with recent experimental results. Geometry optimizations reveal that any asymmetry within the axial O-Ti-O chain is negligible. The band gap in the optimized model corresponds to a O(2p) --> Tibulk(3d) transition. The results suggest that the three Ti atom, single chain, symmetric, finite cluster is an effective model for the geometric and electronic properties of bulk and end TiO6 groups in ETS-10.