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تسجيل مستخدم جديدCorrelation effects and the high-frequency spin susceptibility of an electron liquid: Exact limits
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Spin correlations in an interacting electron liquid are studied in the high-frequency limit and in both two and three dimensions. The third-moment sum rule is evaluated and used to derive exact limiting forms (at both long- and short-wavelengths) for the spin-antisymmetric local-field factor, $lim_{omega to infty}G_-({bf q, omega})$. In two dimensions $lim_{omega to infty}G_-({bf q, omega})$ is found to diverge as $1/q$ at long wavelengths, and the spin-antisymmetric exchange-correlation kernel of time-dependent spin density functional theory diverges as $1/q^2$ in both two and three dimensions. These signal a failure of the local-density approximation, one that can be redressed by alternative approaches.
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