Exponential Regular Approximation

Figure 1. The Exponential Regular Approximation (ERA with y= 1), the Zeroth-Order-Regular Approximation (ZORA), and the Kinetic-Energy Balance Condition (KEBC) ansatz functions for uranium (Z = 92). The distance R is given in bohrs.

Energies obtained using the exponential regular approximation (ERA) Hamiltonian are given in Table 3. The ERA model has one parameter that can be freely... 

In the derivation of the regular solution model the vibrational contribution to the excess properties has been neglected. However, as a first approximation the vibrational contribution can be taken as independent of the interaction between the different atoms, and this contribution can be factored out of the exponential and taken into account explicitly. The partition function of the solution is then given as... 

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