Theoretical Study of the Structure and Electronic Properties of Si3On(-) and Si6On(-) (n = 1-6) Clusters. Fragmentation and Formation Patterns

William Tiznado; Ofelia B Oña; María C Caputo; Marta B Ferraro; Patricio Fuentealba

doi:10.1021/ct900320r

Theoretical Study of the Structure and Electronic Properties of Si3On(-) and Si6On(-) (n = 1-6) Clusters. Fragmentation and Formation Patterns

J Chem Theory Comput. 2009 Sep 8;5(9):2265-73. doi: 10.1021/ct900320r.

Authors

William Tiznado¹, Ofelia B Oña¹, María C Caputo¹, Marta B Ferraro¹, Patricio Fuentealba¹

Affiliation

¹ Departamento de Ciencias Químicas, Facultad de Ecología y Recursos Naturales, Universidad Andres Bello, Av. República 275, Santiago-Chile, Departamento de Física, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Universitaria - Pab. I., Argentina, and Departamento de Física, Universidad de Chile, Las Palmeras 3425, Santiago-Chile.

PMID: 26616613
DOI: 10.1021/ct900320r

Abstract

A theoretical study of two series of small clusters, Si3On(-) and Si6On(-) (n = 1-6), has been carried out. The minimum energy structures were produced adding an electron to neutral species followed by relaxation at the B3LYP-6-311G(2d) level. The vertical ionization energies (VIEs) were computed using the electron propagator theory (EPT) in two approximations, Unrestricted Outer Valence Green Functions (UOVGF) and partial third-order approximation (P3). In the series Si3On(-) the theoretical VIEs of the minimum energy structures agree well with experimental data. For the second series there are not experimental VIEs, and the theoretical results are predictions. The performance of EPT methodologies in conjunction with all-electron or pseudopotentials (PP) calculations is analyzed. The conjunction of P3 and PP approximation proves to be the most efficient and economical methodology to calculate the VIEs of small anionic silicon oxide clusters. In the series Si6On(-) different channels of fragmentation have been calculated. The results suggest that the fragments do not have drastic geometric changes and the anionic fragment corresponds to the atoms where the spin density of the initial large cluster is localized. The Fukui function calculated over selected optimized fragments predicts adequately the interaction between them to form large stable clusters.