Accuracy of Mean Field Approximations for Atomsand
نویسنده
چکیده
We estimate the accuracy of the mean eld approximation induced by the Thomas-Fermi potential for the ground state energy of atoms and molecules. Taking the Dirac exchange correction into account, we show the error to be of the form O(Z 5=3?) + D for any < 2=231 as the total nuclear charge Z becomes large. D is an electrostatic energy of the diierence density that measures the deviation of the mean eld ground state from self-consistency.
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