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South African Journal of Chemistry

versão On-line ISSN 1996-840X
versão impressa ISSN 0379-4350

S.Afr.j.chem. (Online) vol.63  Durban  2010

 

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

 

 


ABSTRACT

An NBO analysis of the electron distribution in the DFT-optimized geometries of different Cp2TiIV(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 TiL π-donation. The out of plane folding for maximum TiL π donation increases with larger Ti-L bond lengths: Cp2TiIV(O,O'-BID) (~35 °) < Cp2TiIV(S,S'-BID) (47 ° average) < Cp2TiIV(Se,Se'-BID) (50 ° average).

Keywords: Gaussian, NBO, titanocene


 

 

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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16 In order to access the extent of donated and/or backdonated charges, single point calculations for the ligand and the metallic fragment with their frozen geometry in the complex were done. The increase in the natural charge on L and the decrease of the natural charge on Ti gave the same results as above: increase in the natural charge on L: 0.227 e (O) < 0.555 e (S) < 0.586 e (Se), decrease in the natural charge on Ti: 0.230 e (O) < 0.527 e (S) = 0.520 e (Se).

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

 

 

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

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