| Numéro |
J. Phys. IV France
Volume 7, Numéro C2, Avril 1997
Proceedings of the 9th International Conference on X-Ray Absorption Fine Structure
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|---|---|---|
| Page(s) | C2-621 - C2-622 | |
| DOI | https://doi.org/10.1051/jp4/1997117 | |
Proceedings of the 9th International Conference on X-Ray Absorption Fine Structure
J. Phys. IV France 7 (1997) C2-621-C2-622
DOI: 10.1051/jp4/1997117
1 LURE, Bât. 209D, Université de Paris-Sud, 91405 Orsoy, France
2 Dip. Scienze Chimiche, via S. Agostino 1, 62032 Camerino (MC), Italy
3 Dip. Matematica e Fisica, via Madonna delle Carceri, 62032 Camerino (MC), Italy
© EDP Sciences 1997
J. Phys. IV France 7 (1997) C2-621-C2-622
DOI: 10.1051/jp4/1997117
XAS Studies on "Costa Type" Model Compounds of Coenzyme B12
M. Giorgetti1, 2, M. Berrettoni2, R. Marassi2, A. Di Cicco3 and I. Ascone11 LURE, Bât. 209D, Université de Paris-Sud, 91405 Orsoy, France
2 Dip. Scienze Chimiche, via S. Agostino 1, 62032 Camerino (MC), Italy
3 Dip. Matematica e Fisica, via Madonna delle Carceri, 62032 Camerino (MC), Italy
Abstract
We report XAS studies on several "Costa type" compounds with different alkyl groups in the axial
position. Especially the XANES part of the spectra shows differences in the electronic and structural features due to
the different electronic donor power of the substituent and to a variation of the degree of the octahedral symmetry
around the metal site. The EXAFS analysis, performed by using the package GNXAS, has permitted the study of the
Co-C bond length dependence on the chemical nature of the alkyl group. The bond length appears to depend on the
Taft σ* constant of the alkyl group. The relationship between the information obtained by EXAFS and XANES
analysis is also discussed.
© EDP Sciences 1997