Radicals as hydrogen bond donors and acceptors

Article

Abstract

High-level quantum chemical techniques were used to study the hydrogen bonding interactions in dimers of simple hydrogen bond donors and acceptors. The dimers studied were formed from combinations of CH4, NH3, OH2 with each other and with the CH3, NH2, and OH radicals. It was found that complexes in which a radical serves as a hydrogen bond donor, i.e.AHx-BHy, are more strongly bound than dimers in which the hydrogen bond donor is the analogous parent molecule, i.e. AHx+1-BHy. Complexes in which a radical serves as a hydrogen bond acceptor, i.e. BHyAHx, are more weakly bound than dimers in which the hydrogen bond acceptor is the analogous parent molecule, i.e. BHy-AHx+1. The differences in these binding properties are attributable to the facts that, in radicals, the A-H bonds are more polar and the A atoms have less negative partial charges than in molecules. Detailed analyses of spin densities revealed that spin delocalization from a radical to a molecule is negligible. Therefore, spin delocalization plays no role in the binding within the complexes studied in this work. Density functional theory methods were also used to calculate the binding energies of the complexes. It was found that the PBE0 and B971 functionals predict binding energies that are in good agreement with the high-level wavefunction data, whereas the performance of the common B3LYP method is not as good. Correcting the functionals for their ability to treat dispersion interactions in carbon-containing compounds improves the binding energies computed with the B3LYP and PBE0 functionals but results in over-binding with B971.

Key words

hydrogen bonding radical coupled-cluster theory wavefunction complete basis set limit density-functional theory molecule-radical complex intermolecular interactions dispersion correcting potentials dispersion corrections 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. [1]
    Adamo, C., Barone, V.J. 1999. Toward reliable density functional methods without adjustable parameters: The PBE0 model. J Chem Phys 110, 6158–6170. This method is sometimes described as “PBE1PBE”.CrossRefGoogle Scholar
  2. [2]
    Avila, D.V., Ingold, K.U., Lusztyk, J., Green, W.H., Procopio, D.R. 1995. Dramatic solvent effects on the absolute rate constants for the abstraction of the hydroxylic hydrogen-atom from tert-butyl hydroperoxide and phenol by the cumyloxyl radical-the role of hydrogen-bonding. J Am Chem Soc 117, 2929–2930.CrossRefGoogle Scholar
  3. [3]
    Bally, T., Borden, W.T. 1999. Calculations on openshell molecules: a beginner’s guide. In: Lipkowitz, K.B., Boyd, D.B. (eds) Reviews in Computational Chemistry, vol 13. John Wiley and Sons, New York, 1–99.CrossRefGoogle Scholar
  4. [4]
    Becke, A.D. 1993. Density-functional thermochemistry. 3. The role of exact exchange. J Chem Phys 98, 5648–5652.CrossRefGoogle Scholar
  5. [5]
    Boys, S.F., Bernardi, F. 1970. Calculation of small molecular interactions by differences of separate total energies-some procedures with reduced errors. Mol Phys 19, 553–566.CrossRefGoogle Scholar
  6. [6]
    Cohen, A.J., Mori-Sánchez, P., Yang, W. 2007. Development of exchange-correlation functionals with minimal many-electron self-interaction error. J Chem Phys 126, 191109.CrossRefPubMedGoogle Scholar
  7. [7]
    Cohen, A.J., Mori-Sánchez, P., Yang, W. 2008. Fractional charge perspective on the band gap in density-functional theory. Phys Rev B 77, 115123.CrossRefGoogle Scholar
  8. [8]
    DiLabio, G.A. 2008. Accurate treatment of van der Waals interactions using standard density functional theory methods with effective core-type potentials: Application to carbon-containing dimers. Chem Phys Lett 455, 348–353.CrossRefGoogle Scholar
  9. [9]
    DiLabio, G.A., Ingold, K.U. 2005. A theoretical study of the iminoxyl/oxime self-exchange reaction. A five-center, cyclic proton-coupled electron transfer. J Am Chem Soc 127, 6693–6699.CrossRefPubMedGoogle Scholar
  10. [10]
    DiLabio, G.A., Johnson, E.R. 2007. Lone pair-pi and pi-pi interactions play an important role in protoncoupled electron transfer reactions. J Am Chem Soc 129, 6199–6203.CrossRefPubMedGoogle Scholar
  11. [11]
    Foti, M.C., Johnson, E.R., Vinquist, M.R., Wright, J.S., Barclay, L.R.C., Ingold, K.U. 2002. Naphthalene diols: A new class of antioxidants intramolecular hydrogen bonding in catechols, naphthalene diols, and their aryloxyl radicals. J Org Chem 67, 5190–5196.CrossRefPubMedGoogle Scholar
  12. [12]
    Frisch, M.J. et al. 2004. Gaussian 03, Revision C.02. Gaussian, Inc., Wallingford CT.Google Scholar
  13. [13]
    Hamprecht, F.A., Cohen, A.J., Tozer, D.J., Handy, N.C. 1998. Development and assessment of new exchange-correlation functionals. J Chem Phys 109, 6264–6271.CrossRefGoogle Scholar
  14. [14]
    Johnson, E.R., Clarkin, O.J., DiLabio, G.A. 2003. Density functional theory based model calculations for accurate bond dissociation enthalpies. 3. A single approach for X-H, X-X, and X-Y (X, Y=C, N, O, S, halogen) bonds. J Phys Chem A 107, 9953–9963.CrossRefGoogle Scholar
  15. [15]
    Johnson, E.R., DiLabio, G.A. 2006. Structure and binding energies in van der Waals dimers: Comparison between density functional theory and correlated ab initio methods. Chem Phys Lett 419, 333–339.CrossRefGoogle Scholar
  16. [16]
    Johnson, E.R., McKay, D.J.J., DiLabio, G.A. 2007. Hydrogen-bond strengths in large complexes: Efficient calculations using locally dense basis sets. Chem Phys Lett 435, 201–207.CrossRefGoogle Scholar
  17. [17]
    Johnson, E.R., Wolkow, R.A., DiLabio, G.A. 2004. Application of 25 density functionals to dispersion-bound homomolecular dimers. Chem Phys Lett 394, 334–338.CrossRefGoogle Scholar
  18. [18]
    Lee, C., Yang, W., Parr, R.G. 1988. Development of the Colle-Salvetti correlation-energy formula into a functional of the electron-density. Phys Rev B 37, 785–789.CrossRefGoogle Scholar
  19. [19]
    Lucarini, M., Mugnaini, V., Pedulli, G.F., Guerra, M. 2003. Hydrogen-bonding effects on the properties of phenoxyl radicals. An EPR, kinetic, and computational study. J Am Chem Soc 125, 8318–8329.CrossRefPubMedGoogle Scholar
  20. [20]
    Mackie, I.D., DiLabio, G.A. 2008. Interactions in large, polyaromatic hydrocarbon dimers: Application of density functional theory with dispersion corrections. J Phys Chem A 112, 10968–10976.CrossRefPubMedGoogle Scholar
  21. [21]
    Martin, J.M.L. 1996. Ab initio total atomization energies of small molecules-Towards the basis set limit. Chem Phys Lett 259, 669–678.CrossRefGoogle Scholar
  22. [22]
    Mayer, J.M., Hrovat, D.A., Thomas, J.L., Borden, W.T. 2002. Proton-coupled electron transfer versus hydrogen atom transfer in benzyl/toluene, methoxyl/methanol, and phenoxyl/phenol selfexchange reactions. J Am Chem Soc 124, 11142–11147.CrossRefPubMedGoogle Scholar
  23. [23]
    Mulder, P., Korth, H.G., Ingold, K.U. 2005. Why quantum-thermochemical calculations must be used with caution to indicate a ‘promising lead antioxidant’. Helv Chim Acta 88, 370–374.CrossRefGoogle Scholar
  24. [24]
    Proshlyakov, D.A., Pressler, M.A., DeMaso, C., Leykam, J.F., DeWitt, D.L., Babcock, G.T. 2000. Oxygen activation and reduction in respiration: Involvement of redox-active tyrosine 244. Science 290, 1588–1591.CrossRefPubMedGoogle Scholar
  25. [25]
    Ruiz, E., Salahub, D.R., Vela, A. 1996. Charge-transfer complexes: Stringent tests for widely used density functionals. J Phys Chem 100, 12265–12276.CrossRefGoogle Scholar
  26. [26]
    Sham, L.J., Schluter, M. 1985. Density-functional theory of the band-gap. Phys Rev B 32, 3883–3889.CrossRefGoogle Scholar
  27. [27]
    Stubbe, J., Nocera, D.G., Yee, C.S., Chang, M.C.Y. 2003. Radical initiation in the class I ribonucleotide reductase: Long-range proton-coupled electron transfer? Chem Rev 103, 2167–2201.CrossRefPubMedGoogle Scholar
  28. [28]
    Wright, J.S., Johnson, E.R., DiLabio, G.A. 2001. Predicting the activity of phenolic antioxidants: Theoretical method, analysis of substituent effects, and application to major families of antioxidants. J Am Chem Soc 123, 1173–1183.CrossRefPubMedGoogle Scholar
  29. [29]
    Wu, Q., Van Voorhis, T. 2006. Constrained density functional theory and its application in long-range electron transfer. J Chem Theory Comput 2, 765–774.CrossRefGoogle Scholar

Copyright information

© International Association of Scientists in the Interdisciplinary Areas and Springer-Verlag GmbH 2009

Authors and Affiliations

  1. 1.Department of ChemistryDuke UniversityDurhamUSA
  2. 2.National Institute for NanotechnologyNational Research Council of CanadaEdmonton, AlbertaCanada

Personalised recommendations