Theoretical analyses of O2/H2O systems under normal and supercritical conditions Academic Article uri icon

abstract

  • We show that a solution of O2 in supercritical water at 850 K and 250 bar is a 'weakly attractive' system, in terms of the classification scheme of Debenedetti et al. This means that some solvent enrichment around the solute does occur but the partial molar volume of the latter is positive. We have investigated the interaction of individual O2 and H2O molecules by both ab initio and non-local density functional methods, and confirmed that the O2 H2O complex is weak (binding energy 1.3 kcal/mol) and loose. The molecular electrostatic potentials of O2 and H2O show the former to have extremely weak negative regions. Molecular dynamics simulations for water and for O2/H2O solutions under both normal (300 K, 1 bar) and supercritical (850 K, 250 bar) conditions show that O2 expands the volume of the supercritical water and decreases the extent of clustering of the water molecules. 1994.

published proceedings

  • Chemical Physics Letters

author list (cited authors)

  • Seminario, J. M., Concha, M. C., Murray, J. S., & Politzer, P.

citation count

  • 30

complete list of authors

  • Seminario, Jorge M||Concha, Monica C||Murray, Jane S||Politzer, Peter

publication date

  • May 1994