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A new, simple method for the extraction of specific interaction enthalpy from the enthalpy of solvation is proposed. It is based on empirical but very general relationships describing the non-specific solvation enthalpy. The specific interaction enthalpy is calculated from the solution enthalpies in the solvent under consideration, cyclohexane and tetrachloromethane. The solution enthalpy of at least one linear alkane in the solvent must also be available. The solution enthalpies of a 'model compound' or homomorph are not required. This method is applicable not only for proton-donor solutes but also for acceptor solutes such as iodine. It can be used also for solvents associated by hydrogen bonding (e.g. alcohols). The enthalpies of specific interaction for 280 solute-solvent systems were calculated. Solution enthalpy data were mainly obtained from the literature and partially measured by the authors. The results were compared with literature data on complexation enthalpy.

Hydrogen bonding in pure aliphatic alcohols is investigated using a novel calorimetric approach. Average enthalpies of hydrogen bonding were determined for methanol, ethanol, propan‐1‐ol, propan‐2‐ol, butan‐1‐ol, hexan‐1‐ol and octan‐1‐ol. For all the studied alcohols except methanol the average hydrogen‐bonding enthalpies fall in the range from −16.9 to −17.7 kJ mol−1. A slightly smaller value of −15.1 kJ mol−1 was observed for methanol. From the enthalpies of the specific interactions of the alcohols and chloroform (as proton donors) formed with the alcohols and diethyl ether (as proton acceptors), the dimerization enthalpies were determined for the investigated alcohols: −8.6 ± 0.7 kJ mol−1. The specific interaction and dimerization enthalpies obtained are concurrent with the Badger–Bauer rule and the hydrogen‐bond cooperativity effects. The calorimetric data obtained are supported by literature Fourier transform infrared data on dimer and multimer formation for ethanol and octan‐1‐ol in tetrachloromethane solution. Copyright © 2005 John Wiley & Sons, Ltd.

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The paper is mainly the review and generalization of the previous publications of the authors. It demonstrates that solution calorimetry method gives the opportunities of more detailed understanding of various aspects of intermolecular interactions in solution. We are assured that prerequisite to such an understanding is the successive analysis of various solute–solvent systems from the simplest ones which include alkanes as a solute or as a solvent to the most complex systems with solvent self‐association via hydrogen bonding. Particular findings discussed in this paper are (i) an inconspicuous contribution of electrostatic solute–solvent interaction to the solvation enthalpy and, accordingly, the dominating contribution of dispersion interactions for nonspecifically solvated solutes; (ii) new, very general method for the extraction of specific interaction enthalpy from the enthalpy of solvation; (iii) new method of determination of self‐association enthalpies for the solvents associated via hydrogen bonding; (iv) new method for determination of cooperative hydrogen bonding enthalpies of proton acceptors with associated species of alcohols; (v) the unique method of experimental determination of the hydrophobic effect enthalpy. Copyright © 2007 John Wiley & Sons, Ltd.

A calorimetric method for the determination of cooperative hydrogen bonding (HB) enthalpy of proton acceptors (B) with associated species of alcohols is proposed. The average enthalpy of cooperative HB of pyridine with associated species of alcohols was found to be À19.8 AE 0.6 kJ mol À1 for all alcohols investigated. This value exceeds the enthalpy of HB in the complex ROH . . . NC 5 H 5 (the average for all alcohols is À15.8 AE 0.2 kJ mol À1 ) by 20-30%. Cooperativity factors (A b , A Ox ) of hydrogen bonds for (ROH) 2 . . . NC 5 H 5 complexes were determined using the IR-spectroscopic method. The average values for the alcohols under consideration were found to be A b ¼ 1.41 AE 0.04 and A Ox ¼ 1.54 AE 0.05. On the basis of IR-spectroscopic and calorimetric data, the enthalpy of cooperative interactions of pyridine with the dimer (ROH) 2 was estimated. This value for all the alcohols studied is, on average, À20.9 AE 0.1 kJ mol À1 .

Recently, the solution calorimetry has been shown to be a valuable tool for the indirect determination of vaporization or sublimation enthalpies of low volatile organic compounds. In this work we studied 16 halogen-substituted derivatives of benzene, naphthalene, biphenyl, and anthracene using a new solution calorimetry based approach. Enthalpies of solution at infinite dilution in benzene as well as molar refractions for the chlorine-, bromine-, and iodine-substituted aromatics were measured at 298.15 K. Vaporization and sublimation enthalpies of these compounds at 298.15 K were indirectly derived from the solution calorimetry data. In order to verify results obtained by using solution calorimetry, vaporization/sublimation enthalpies for 1,2-, 1,3-, 1,4-dibromobenzenes, 4-bromobiphenyl, and 4,4′-dibromobiphenyl were additionally measured by using the well established transpiration method. Experimental data available in the literature were collected and evaluated in this work for the sake of comparison with our own results. Vaporization and sublimation enthalpies of halogen-substituted aromatics under study derived by using solution calorimetry approach have been in a good agreement with those measured by conventional methods. This fact approves using of solution calorimetry for determination or validation of sublimation/vaporization enthalpies for different aromatic compounds at reference temperature 298.15 K, where the conventional experimental data are absent or in disarray. Evaluated in this work a data set has been used to establish a simple group additivity scheme for prediction of vaporization enthalpies for halogen-substituted aromatic hydrocarbons.

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