Spin-polarised SCC-Xα calculations for electronic- and magnetic-structure properties of (2Fe-2S) ferredoxin models

R. Blas*, J. Guillin, E. L. Bominaar, M. Grodzicki, V. R. Marathe, A. X. Trautwein

*Corresponding author for this work
14 Citations (Scopus)


The spin-polarised SCC-X alpha method is used for the evaluation of electronic- and magnetic-structure properties (i.e., electron densities at the iron nuclei, electric-field gradients, g factors and magnetic hyperfine tensors) of oxidised and reduced (2Fe-2S) ferredoxin models, represented by the structure formula ((SR)2FeS2Fe(SR)2) (n=-2, -3), with R=H, CH3 and (C6H4(CH 2)2)12/. A strong geometry dependence of charge and spin densities, and their related properties, is found for minimal cluster size (R=H) on the position of the terminal hydrogen atoms. A Fe-S-H bond angle of about 90' turned out to be preferable to 180'. Experimental hyperfine data of synthetic analogues and of ferredoxins are in reasonable agreement with corresponding calculated properties obtained for the (2Fe-2S) ferredoxin models mentioned above. Comparing experimental and calculated g factors of reduced (2Fe-2S) centres indicates that the model clusters used are of gav approximately 1.91 type. Finally, the exchange-coupling constant J between the two iron ions in the oxidised (2Fe-2S) ferredoxin model is estimated from the difference in the total energy between the high-spin and broken-spin symmetry states of the model.

Original languageEnglish
Article number013
JournalJournal of Physics B: Atomic and Molecular Physics
Issue number21
Pages (from-to)5627-5637
Number of pages11
Publication statusPublished - 01.12.1987


Dive into the research topics of 'Spin-polarised SCC-Xα calculations for electronic- and magnetic-structure properties of (2Fe-2S) ferredoxin models'. Together they form a unique fingerprint.

Cite this