Generalized-Gradient-Functional Treatment of String in Density- Functional Perturbation Theory

01 January 2005

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The direct calculation of elastic and piezoelectric tensors utilizing densityfunctional perturbation theory has been extended to encompass generalized- gradientapproximation functionals. Expressions for the first- and second-order exchangecorrelation potentials and energies are found to have structures unique to the strain perturbation.