Nitroxyl and its anion in aqueous solutions: Spin states, protic equilibria, and reactivities toward oxygen and nitric oxide -- Data Supplement - Supporting Information -- Proceedings of the National Academy of Sciences

Supporting information for Shafirovich and Lymar (May 21, 2002) Proc. Natl. Acad. Sci. USA, 10.1073/pnas.112202099.

Note 3.
The gas phase value for k₉ at room temperature has been reported as 0.9 × 10⁶ M^–1•s^–1 (1, 2). Thus, the ratio (k₉)_water/(k₉)_gas is approximately 9. For a reaction between a pair of neutral molecules with low affinity for water (like in reaction 9), the activated complex theory gives an approximate correlation (k₉)_water/(k₉)_gas = exp{–D_hydrG⁰(¹HNO)/RT} (see ref. 3). Application of this correlation yields D_hydrG⁰(¹HNO) = –5.5 kJ/mol, which is very close to the value based on analogy with HCN and used in developing Fig. 1.

References:

1. Bryukov, M. G., Kachanov, A. A., Timonnen, R., Seetula, J., Vandoren, J. & Sarkisov, O. M. (1993) Chem. Phys. Lett. 208, 392–398.

2. Cheskis, S. G., Nadtochenko, V. A. & Sarkisov, O. M. (1981) Int. J. Chem. Kinet. 13, 1041–1050.

3. Weston, R. E., Jr. & Schwarz, H. A. (1972) Chemical Kinetics (Prentice-Hall, Englewood Cliffs, NJ).