Hirschfelder partitioning

Table 1. Charge distribution in free methane as given by DFT (Hirschfeld partitioned charges, Mulliken population analysis, ESP fitted charges) and MOPAC calculations.

N-particle systems. The classical partition function Z (T) of a canonical ensemble of N molecules is given by [184] (Hirschfelder et al. 1956)... 

Certain PN, Hirschfelder JO (1970) New partitioning perturbation theory. III. Applications to electron exchange. J Chem Phys 52 5992-5999... 

Prigogine (19r)7) applied the partition function of Eyriiig and Hirschfelder (1.937) and used Lennard-,Johns potential as the potential energy between two molecules (mers)... 

Once the mean potential to r) is known, we may use the general relations (7.1.3)-(7.1.6) to compute the thermod3mamic functions. This can imfortunately not be done in closed form because of the complicated analytical form of the mean potential. However, tables of the cell partition function W and its derivatives with respect to volume and temperature now exist (Lennard-Jones and Devonshire [1937, 1938], Hill [1947], Prigogine and Garikian [1948], Wentorf, Buehler, Hirschfelder and Curtiss [1950], Hirschfelder, Curtiss and Bird [1954]), which permit to compare the Lennard-Jones and Devonshire theory with experimental data. 

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