Geometric and Electronic Structures of Vanadium Sub-nano Clusters, Vn (n = 2-5), and their Adsorption Complexes with CO and O2 Ligands: A DFT-NBO Study

Document Type : Regular Article

Authors

Department of Chemistry, College of Science, Shiraz University, Eram Square, Eram Street, 7146713565, Shiraz, Iran

Abstract

In this study, electronic structures of ground state of pure vanadium sub-nano clusters, Vn (n=2-5), and their interactions with small ligands for example CO and triplet O2 molecules are investigated by using density functional theory (DFT) calibration at the mPWPW91/QZVP level of theory. The favorable orientations of these ligands in interaction with pure vanadium sub-nano clusters were determined. Multiplicities of these pure clusters are triple, doublet, singlet and doublet for dimer, trimer, tetramer and pentamer, respectively. While the CO molecule is associatively adsorbed on vanadium clusters, triplet O2 is dissociated over adsorption. Primary and secondary hyper-conjugation concepts have been employed to show stabilization of vanadium oxide complexes. Natural bond orbital (NBO) and natural resonance theory (NRT) analysis revealed that trimer, tetramer and pentamer clusters are relatively delocalized and have some resonance structures.

Graphical Abstract

Geometric and Electronic Structures of Vanadium Sub-nano Clusters, Vn (n = 2-5), and their Adsorption Complexes with CO and O2 Ligands: A DFT-NBO Study

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Main Subjects


Volume 5, Issue 3 - Serial Number 15
September 2017
Pages 601-615
  • Receive Date: 18 March 2017
  • Revise Date: 29 April 2017
  • Accept Date: 28 May 2017
  • First Publish Date: 01 September 2017