open access

https://hdl.handle.net/2115/81206

Spin-inversion mechanisms in O-2 binding to a model heme complex revisited by density function theory calculations

英語

spin inversion

2020-04-30

John Wiley & Sons

Journal of Computational Chemistry

41(11)

1130-1138

Spin-inversion mechanisms in O-2 binding to a model heme complex, consisting of Fe(II)-porphyrin and imidazole, were investigated using density-functional theory calculations. First, we applied the recently proposed mixed-spin Hamiltonian method to locate spin-inversion structures between different total spin multiplicities. Nine spin-inversion structures were successfully optimized for the singlet-triplet, singlet-quintet, triplet-quintet, and quintet-septet spin-inversion processes. We found that the singlet-triplet spin-inversion points are located around the potential energy surface region at short Fe-O distances, whereas the singlet-quintet and quintet-septet spin-inversion points are located at longer Fe-O distances. This suggests that both narrow and broad crossing models play roles in O-2 binding to the Fe-porphyrin complex. To further understand spin-inversion mechanisms, we performed on-the-fly Born-Oppenheimer molecular dynamics calculations. The reaction coordinates, which are correlated to the spin-inversion dynamics between different spin multiplicities, are also discussed.

学術雑誌論文

Accepted Manuscript

This is the peer reviewed version of the following article: Saito, K, Watabe, Y, Fujihara, T, Takayanagi, T, Hasegawa, J‐y. Spin‐inversion mechanisms in O2 binding to a model heme complex revisited by density function theory calculations. J Comput Chem. 2020; 41: 1130– 1138, which has been published in final form at https://doi.org/10.1002/jcc.26159 . This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions."

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