Cover: Convergence of the Series Expansion Solution to the Thomas-Fermi-Dirac Equation.

Convergence of the Series Expansion Solution to the Thomas-Fermi-Dirac Equation.

Published 1970

by James E. Enstrom

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Studies the convergence of the power series solution to determine precisely the region in which it is accurate. The Thomas-Fermi-Dirac statistical model has been used for approximate calculations of potential fields and charge densities. It has also been used to derive the equation of state of matter at high pressures and at various temperatures. The second-order nonlinear differential equation that results from the model can only be solved numerically. This is done most accurately by expressing the solution as a power series expanded about the origin. Beyond a certain radius, the series diverges and the solution must be continued by numerical integration. 6 pp. (KB)

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