RESEARCH ARTICLE

 

A DFT and NBO analysis of the bonding in titanocenyl complexes containing a five-membered L,L'-cyclic ligand: L,L' = O,O'; S,S' or Se,Se'

 

 

Jeanet Conradie^*

Department of Chemistry, University of the Free State, Bloemfontein 9301, South Africa

 

 

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ABSTRACT

An NBO analysis of the electron distribution in the DFT-optimized geometries of different Cp₂Ti^IV(L,L'-BID) complexes with L,L'-BID = dioxolene, dithiolene or diselenolene, showed that a large degree of folding along the L^...L axis is needed for sufficient Ti←L π-donation. The out of plane folding for maximum Ti←L π donation increases with larger Ti-L bond lengths: Cp₂Ti^IV(O,O'-BID) (~35 °) < Cp₂Ti^IV(S,S'-BID) (47 ° average) < Cp₂Ti^IV(Se,Se'-BID) (50 ° average).

Keywords: Gaussian, NBO, titanocene

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Full text available only in PDF format.

 

Acknowledgements

Financial assistance by the South African National Research Foundation, under grant number 2067416, and the Central Research Fund of the University of the Free State is gratefully acknowledged.

 

References and Notes

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Received 4 August 2009
Revised 2 February 2010
Accepted 29 May 2010

 

 

* E-mail: conradj@ufs.ac.za