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C..2 B86MGC: X $\alpha\beta\gamma$ with Modified Gradient Correction

B86 with modified gradient correction for large density gradients. See reference [8] for more details.

\begin{dmath} K= \sum_s -c \left( \rho_{s} \right) ^{4/3}-{\frac {\beta\, \left(... ...{ \left( 1+\lambda\, \left( \chi_{s} \right) ^{2} \right) ^{4/5}}} ,\end{dmath} where \begin{dmath} c=3/8\,\sqrt [3]{3}{4}^{2/3}\sqrt [3]{{\pi }^{-1}} ,\end{dmath} \begin{dmath} \beta= 0.00375 \end{dmath} and \begin{dmath} \lambda= 0.007 .\end{dmath} To avoid singularities in the limit $\rho_{\bar{s}}\rightarrow 0$ \begin{dmath} G= -c \left( \rho_{s} \right) ^{4/3}-{\frac {\beta\, \left( \chi_{... ...{ \left( 1+\lambda\, \left( \chi_{s} \right) ^{2} \right) ^{4/5}}} .\end{dmath}

molpro@molpro.net
Oct 10, 2007