title: Phenol-quinone tautomerism in (arylazo)naphthols and the analogous Schiff bases: benchmark calculations.
abstract: Tautomerization energies of a series of isomeric [(4-R-phenyl)azo]naphthols and the analogous Schiff bases (R = N(CH3)2, OCH3, H, CN, NO2) are calculated by LPNO-CEPA/1-CBS using the def2-TZVPP and def2-QZVPP basis sets for extrapolation. The performance of various density functionals (B3LYP, M06-2X, PW6B95, B2PLYP, mPW2PLYP, PWPB95) as well as MP2 and SCS-MP2 is evaluated against these results. M06-2X and SCS-MP2 yield results close to the LPNO-CEPA/1-CBS values. Solvent effects (CCl4, CHCl3, CH3CN, and CH3OH) are treated by a variety of bulk solvation models (SM8, IEFPCM, COSMO, PBF, and SMD) as well as explicit solvation (Monte Carlo free energy perturbation using the OPLSAA force field).
authors.affiliation: Department of Chemistry, Federal Urdu University of Arts, Science & Technology , Karachi, Sindh, Pakistan.
authors.forename: S Tahir
authors.initials: ST
authors.lastname: Ali
authors.forename: Liudmil
authors.initials: L
authors.lastname: Antonov
authors.forename: Walter M F
authors.initials: WM
authors.lastname: Fabian