Matrix Isolation Infrared Spectrum of the Sulfuric Acid-Monohydrate Complex: New Assignments and Resolution of the Missing H-Bonded v(OH) Band Issue

The matrix isolation infrared spectra of dry and wet vapors of sulfuric acid have been investigated as trapped in solid argon matrices. The availability of a spectrum of trapped anhydrous acid vapor and its comparison with the spectra of trapped water containing vapors of the acid allowed the identification of the hydrogen-bonding shifted hydroxyl bands for both the acid and the water moieties of the monohydrated H2SO4 center dot H2O complex. The experimental results are compared to the various theoretically calculated wavenumber values of the acid and its monohydrated complex. The complex stabilization energies, as obtained from calculations and empirical correlations, are compared.