Nitrogenase Structure and Function Relationships by Density Functional Theory

  • Travis V. HarrisEmail author
  • Robert K. Szilagyi
Part of the Methods in Molecular Biology book series (MIMB, volume 766)


Modern density functional theory has tremendous potential with matching popularity in metalloenzymology to reveal the unseen atomic and molecular details of structural data, spectroscopic measurements, and biochemical experiments by providing insights into unobservable structures and states, while also offering theoretical justifications for observed trends and differences. An often untapped potential of this theoretical approach is to bring together diverse experimental structural and reactivity information and allow for these to be critically evaluated at the same level. This is particularly applicable for the tantalizingly complex problem of the structure and molecular mechanism of biological nitrogen fixation. In this chapter we provide a review with extensive practical details of the compilation and evaluation of experimental data for an unbiased and systematic density functional theory analysis that can lead to remarkable new insights about the structure–function relationships of the iron–sulfur clusters of nitrogenase.

Key words

Density functional theory electronic structure exchange functional correlation functional basis set saturation spectroscopic calibration broken symmetry calculation ferromagnetic coupling antiferromagnetic coupling exchange interaction 


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© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Department of Chemistry and BiochemistryAstrobiology Biogeochemistry Research Center, Montana State UniversityBozemanUSA

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