Thermodynamics Research Center / ThermoML | Journal of Chemical Thermodynamics

Experimental and computational study of the molecular energetics of the monoiodoanisole isomers

Lobo Ferreira, A. I. M. C.[Ana I.M.C.], Ribeiro da Silva, M. A. V.[Manuel A. V.]
J. Chem. Thermodyn. 2012, 48, 84-92
ABSTRACT
The standard (p = 0.1 MPa) molar enthalpies of formation, in the condensed phase, of the three monoiodoanisoles, were derived from the respective enthalpies of combustion, measured by rotating-bomb combustion calorimetry. Their enthalpies of sublimation/vaporization, at T = 298.15 K, were obtained by Calvet microcalorimetry using the high-temperature vacuum sublimation technique. Moreover the standard molar enthalpy, entropy and Gibbs energy of sublimation, at T = 298.15 K, of 4-iodoanisole were derived from the Knudsen mass-loss effusion technique. Combining the former sets of experimental results, the standard molar enthalpies of formation in the gas-phase, at T = 298.15 K, of 2-, 3- and 4-iodoanisole were derived, respectively, as: (15.1 +- 2.1) kJ mol-1; (11.8 +- 2.2) kJ mol-1, and (12.4 +- 1.6) kJ mol-1. The experimental values of the gas-phase enthalpies of formation of each iodoanisole were also estimated by means of the empirical scheme developed by Cox and by density functional theory calculations employing the B3LYP/6-311++G(d,p) approach. Estimated values are in excellent agreement with the reported experimental ones derived in the present paper.
Compounds
# Formula Name
1 I2 iodine
2 CO2 carbon dioxide
3 H2O water
4 O2 oxygen
5 C7H7IO 1-iodo-2-methoxybenzene
6 C7H7IO 3-iodoanisole
7 C7H7IO 1-iodo-4-methoxybenzene
Datasets
The table above is generated from the ThermoML associated json file (link above). POMD and RXND refer to PureOrMixture and Reaction Datasets. The compound numbers are included in properties, variables, and phases, if specificied; the numbers refer to the table of compounds on the left.
Type Compound-# Property Variable Constraint Phase Method #Points
  • POMD
  • 5
  • Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Liquid
  • Gas
  • drop calorimetry
  • 1
  • POMD
  • 5
  • Molar enthalpy of transition or fusion, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Liquid
  • Gas
  • drop calorimetry
  • 1
  • POMD
  • 6
  • Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Liquid
  • Gas
  • drop calorimetry
  • 1
  • POMD
  • 6
  • Molar enthalpy of transition or fusion, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Liquid
  • Gas
  • drop calorimetry
  • 1
  • POMD
  • 7
  • Molar enthalpy of vaporization or sublimation, kJ/mol ; Crystal
  • Temperature, K; Crystal
  • Crystal
  • Gas
  • Derived by Second law
  • 1
  • POMD
  • 7
  • Molar enthalpy of vaporization or sublimation, kJ/mol ; Liquid
  • Temperature, K; Liquid
  • Liquid
  • Gas
  • drop calorimetry
  • 1
  • POMD
  • 7
  • Molar enthalpy of transition or fusion, kJ/mol ; Crystal
  • Temperature, K; Crystal
  • Crystal
  • Gas
  • drop calorimetry
  • 1
  • POMD
  • 7
  • Vapor or sublimation pressure, kPa ; Crystal
  • Temperature, K; Crystal
  • Crystal
  • Gas
  • Calculated from knudsen effusion weight loss
  • 26
  • RXND
  • 6
  • 1
  • 2
  • 3
  • 4
  • Specific internal energy of reaction at constant volume, J/g
  • Rotating bomb calorimetry
  • 1
  • RXND
  • 7
  • 1
  • 2
  • 3
  • 4
  • Specific internal energy of reaction at constant volume, J/g
  • Rotating bomb calorimetry
  • 1
  • RXND
  • 5
  • 1
  • 2
  • 3
  • 4
  • Specific internal energy of reaction at constant volume, J/g
  • Rotating bomb calorimetry
  • 1