Two-dimensional thermodynamics descriptors

Binding constants of H-bond complexes are normally used to create H-bond scales [21-23], e.g. in accordance with Ref [22]  

A multiplicative approach to describe the enthalpy and free energy of H-bonding was developed by Raevsky et al. [3, 24—27]. From a large number of their own 

Phenol and hexamethylphoshoramide (HMPA) were selected, respectively, as the standard H-bond donor and H-bond acceptor with their values fixed on free energy and enthalpy H-bond scales for phenol, -2.50 for the H-bond donor enthalpy factor (TJ and also for the H-bond donor free energy factor (Ca) for HMPA, 2.50 for the H-bond acceptor enthalpy factor ( J and 4.00 for the H-bond acceptor free energy factor (CJ. 

Correlations of calculated and experimental enthalpy, and calculated and experimental free energy values for the indicated 936 systems gave the following 

the statishcal criteria for Eqs. (5) and (6) show that the approach provides a reasonably reliable method to calculate H-bond enthalpy and free energy. 

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