New method for determination of vaporization and sublimation enthalpy of aromatic compounds at 298.15 K using solution calorimetry technique and group-additivity scheme

Sublimation Study of Six 5-Substituted-1,10-Phenanthrolines by Knudsen Effusion Mass Loss and Solution Calorimetry

“…Determination of sublimation enthalpies of 5-chloro and 5-methyl-1,10-phenanthrolines is a challenging task since no values are now available in the literature, and it has prompted us to apply a solution calorimetry method for these compounds. The approach for determination of evaporation and sublimation enthalpies based on the relationship between evaporation/sublimation enthalpy of a compound A i , with its solution Δ soln H m A i / S and solvation Δ solv H m A i /S enthalpies in a solvent S was developed and validated in [ 15 , 16 , 27 , 28 ]: Δ cr g H m 0 = Δ soln H m A i / S − Δ solv H m A i / S , …”

“…According to this approach, solvation enthalpy of substituted 1,10-phenanthrolines in benzene can be calculated using the following equation: Δ solv H m A i / S = Δ solv H m ArH / S + Σ Δ solv H m Y i → CH / S + Σ Δ solv H m X i → H / S , where Δ solv H m ArH / S is the solvation enthalpy of a parent aromatic compound, Δ solv H m X i → H / S is the contribution to the solvation enthalpy related to a replacement of the hydrogen atoms by any other groups, and Δ solv H m Y i → CH / S is a contribution to the solvation enthalpy related to a replacement of the CH -group in aromatic rings by any other groups. In the case of the substituted 1,10-phenanthrolines the solvation enthalpies in benzene were calculated as a sum of solvation enthalpy of phenanthrene (−74.6 kJ·mol −1 ) [ 28 ] and the contribution related to the replacement of the CH-fragment in these rings by the specific units for 1,10-phenanthrolines: −N = (−5.4 kJ·mol −1 ) [ 16 ] and the contribution related to the replacement of the H-atom by the CH 3 —group (−3.5 kJ·mol −1 ), and Cl—group (−6.1 kJ·mol −1 ) [ 15 ].…”

“…c Calculated according to Equation (1). Uncertainties of vaporization/sublimation enthalpy are twice standard deviation [ 15 ].…”

“…KEML measurements were performed on the crystal phases of these compounds and sublimation enthalpies derived. Furthermore, in the effort to perform a mutual validation of two completely independent techniques, the solution calorimetry method developed by Solomonov and co-workers [ 15 , 16 ] was also used for two compounds. This method is based on the relationship between evaporation/sublimation enthalpy and enthalpies of solution and solvation of a studied compound in a properly selected solvent.…”

Six-membered ring aliphatic compounds: A search for regularities in phase transitions

“…In order to support transpiration results on sublimation enthalpies we used the independent complementary method based on solution calorimetry measurements [16][17][18][19]. Enthalpies of solution at T = 298.15 K of adamantane, 1-Cl-adamantane, 2-Cl-adamantane, 1-Br-adamantane, and 1-Br- …”