S K-edge XAS and DFT calculations on square-planar NiII-thiolate complexes: effects of active and passive H-bonding. Academic Article uri icon


  • S K-edge XAS for a low-spin NiII-thiolate complex shows a 0.2 eV shift to higher pre-edge energy but no change in Ni-S bond covalency upon H-bonding. This is different from the H-bonding effect we observed in high-spin FeIII-thiolate complexes where there is a significant decrease in Fe-S bond covalency but no change in energy due to H-bonding (Dey, A.; Okamura, T.-A.; Ueyama, N.; Hedman, B.; Hodgson, K. O.; Solomon, E. I. J. Am. Chem. Soc. 2005, 127, 12046-12053). These differences were analyzed using DFT calculations, and the results indicate that two different types of H-bonding interactions are possible in metal-thiolate systems. In the high-spin FeIII-thiolate case, the H-bonding involves a thiolate donor orbital which is also involved in bonding with the metal (active), while in the low-spin NiII-thiolate, the orbital involved in H-bonding is nonbonding with respect to the M-S bonding (passive). The contributions of active and passive H-bonds to the reduction potential and Lewis acid properties of a metal center are evaluated.

published proceedings

  • Inorg Chem

author list (cited authors)

  • Dey, A., Green, K. N., Jenkins, R. M., Jeffrey, S. P., Darensbourg, M., Hodgson, K. O., Hedman, B., & Solomon, E. I.

citation count

  • 13

complete list of authors

  • Dey, Abhishek||Green, Kayla N||Jenkins, Roxanne M||Jeffrey, Stephen P||Darensbourg, Marcetta||Hodgson, Keith O||Hedman, Britt||Solomon, Edward I

publication date

  • November 2007