title: Benchmark Thermodynamic Properties of Methyl- and Methoxybenzamides: Comprehensive Experimental and Theoretical Study.
abstract: The enthalpies of formation of 2-, 3-, and 4-CH3-benzamide, as well as for 2-CH3O-benzamide, were measured by using combustion calorimetry. Vapor pressures of the isomeric CH3- and CH3O-benzamides were measured by using the transpiration method. The enthalpies of sublimation/vaporization of these compounds at 298 K were obtained from temperature dependencies of vapor pressures. The enthalpies of solution of the isomeric CH3- and CH3O-benzamides were measured with solution calorimetry. The enthalpies of sublimation of m- and p-substituted benzamides were independently derived with help of a solution calorimetry-based procedure. The enthalpies of fusion of the CH3-benzamides were derived from differential scanning calorimetry measurements. Thermochemical data on CH3- and CH3O-benzamides were collected, evaluated, and tested for internal consistency. A simple incremental procedure was suggested for a quick appraisal of vaporization enthalpies of substituted benzamides. The high-level G4 quantum-chemical method was used for mutual validation of the experimental and theoretical gas-phase enthalpies of formation. A remarkable ability of the G4-based atomization procedure to calculate reliable enthalpies of formation was established for the set of aliphatic and aromatic amides. An outlook for the proper validation of the G4-AT procedure was discussed.
authors.affiliation: Department of Physical Chemistry and Department "Science and Technology of Life, Light and Matter", University of Rostock , Dr-Lorenz-Weg 1, D-18059, Rostock, Germany.
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Emel'yanenko
authors.affiliation: Department of Physical Chemistry and Department "Science and Technology of Life, Light and Matter", University of Rostock , Dr-Lorenz-Weg 1, D-18059, Rostock, Germany.
authors.forename: Ksenia V
authors.initials: KV
authors.lastname: Zaitseva
authors.affiliation: Department of Physical Chemistry, Kazan Federal University , Kremlevskaya str. 18, 420008 Kazan, Russia.
authors.forename: Ruslan N
authors.initials: RN
authors.lastname: Nagrimanov
authors.affiliation: Department of Physical Chemistry, Kazan Federal University , Kremlevskaya str. 18, 420008 Kazan, Russia.
authors.forename: Boris N
authors.initials: BN
authors.lastname: Solomonov
authors.affiliation: Department of Physical Chemistry and Department "Science and Technology of Life, Light and Matter", University of Rostock , Dr-Lorenz-Weg 1, D-18059, Rostock, Germany.
authors.forename: Sergey P
authors.initials: SP
authors.lastname: Verevkin