Influence of Solute-Solvent Hydrogen Bonding on Intramolecular Magnetic Exchange Interaction in Aminoxyl Diradicals: A QM/MM Broken-Symmetry DFT Study
2009 (English)In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Vol. 113, no 16, 5545-5548 p.Article in journal (Refereed) Published
We have investigated the effect of nitroxide radical-water hydrogen bonding (NO center dot center dot center dot center dot H2O) on the intramolecular magnetic exchange interaction (J) for biologically relevant aminoxyl diradicals. We adopt a combination of broken-symmetry density functional theory and the quantum mechanics/molecular mechanics (QM/MM) approach. We find that the presence of hydrogen bonding reorients the radical spin density on -NO center dot. This phenomenon reduces the effective distance between the two interacting localized spin centers that eventually increases the intramolecular magnetic exchange interaction. We have also investigated the functional variation of the magnetic exchange interaction, using various GGA (BLYP, PBE, HCTH407), meta-GGA (TPSS, VXSC), and hybrid (O3LYP, B3LYP, B3P86, B3PW91, and PBE0) functionals.
Place, publisher, year, edition, pages
2009. Vol. 113, no 16, 5545-5548 p.
IdentifiersURN: urn:nbn:se:uu:diva-129119DOI: 10.1021/jp901922jISI: 000265269100026OAI: oai:DiVA.org:uu-129119DiVA: diva2:337681