Ab initio MP2 and FTIR matrix isolation studies on tert-butanethiol complexes with water

The calculated BSSE corrected interaction energy equals to −4.45 and −1.52 kcal/mol for D1 and D2, respectively, while is between −11.40 and −8.32 kcal/mol for the ternary complexes. An attractive cooperative effect has been found for the cyclic T1 and T2 of ca. −1.6 kcal/mol, while the least stable chain structure T3 is characterized by a small repulsive three-body interaction energy. The comparison of the experimental frequencies with the calculated ones allowed to identify the D1 complex in the argon matrices. The experimental spectra evidenced that both cyclic T1 and T2 structures may also be present.