Theoretical study of neutral and cationic complexes involving phenol

Geometry and interaction energy in complexes of the Ph-L type (L = Ar, N-2, CO, H2O, NH3, CH4, CH3OH, CH3F) involving neutral or cationic phenol were determined using the density functional theory formalism based on the minimization of the total energy bifunctional and gradient-dependent approximations for its exchange-correlation and nonadditive kinetic-energy parts. For the neutral complexes the calculated interaction energies range from 1 kcal/mol for the Ph-Ar complex to about 10 kcal/mol for Ph-NH3. The interactions are stronger if the cationic phenol is involved (up to 25 kcal/mol). It is found, except for neutral Ph-Ar, that the hydrogen-bonded structure is more stable than the pi-bound one. Calculated interaction energies (D-e) correlate well with the experimental dissociation energies (D-0). (C) 2004 Wiley Periodicals, Inc.