KOs2O6: Superconducting rattler
نویسندگان
چکیده
Electronic structure calculations and experimental data point to soft local vibrations of alkali ions in AOs2O6 (A 1⁄4 K, Rb, Cs). Due to its size the potassium ion experiences an extremely anharmonic and broad potential well. We use ab initio energies and forces to derive the Hamiltonian for the dynamics of K ions and solve the single site problem. r 2006 Published by Elsevier B.V.
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