Structural Investigation of Solute−Solute Interactions in Aqueous Solutions of Tertiary Butanol

Hydrogen/deuterium isotopic substitution neutron diffraction techniques have been used to measure the solute−solute intermolecular structural correlations in 0.06, 0.11, and 0.16 mole fraction tertiary butanol−water solutions. Empirical potential structure refinement (EPSR) procedures have been used to extract detailed information relating to the intermolecular structure in these systems. A trend from hydrophobic to hydrophilic character of the solute−solute correlations as a function of solute concentration is observed. Of particular note is the domination of nonpolar to nonpolar solute contacts at 0.06 mole fraction concentration compared with a more complex mixture of nonpolar and polar solute−solute intermolecular contact configurations at the higher alcohol concentration.