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Nature of the spin-singlet ground state in CaCuGe2O6

Roser Valenti·T. Saha-Dasgupta·Claudius Gros
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Abstract

We investigate by means of ab initio electronic structure analysis and Quantum Monte Carlo calculations the scenario where longer-ranged magnetic interactions dominate over short-ranged interactions in the physical description of compounds. This question is discussed, in particular, for the case of CaCuGe$_2$O$_6$ which shows a spin-singlet behavior induced by third nearest neighbor copper pairs.

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Roser Valenti, T. Saha-Dasgupta, Claudius Gros. 2002-09-03. Nature of the spin-singlet ground state in CaCuGe2O6. https://doi.org/10.1103/physrevb.66.054426

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