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Tetrahedra system Cudaca: high-temperature manifold of molecular configurations governing low-temperature properties

338   0   0.0 ( 0 )
 Added by Oksana Zaharko
 Publication date 2008
  fields Physics
and research's language is English




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The Cudaca system composed of isolated Cu2+ S=1/2 tetrahedra with antiferromagnetic exchange should exhibit properties of a frustrated quantum spin system. ab initio density functional theory calculations for electronic structure and molecular dynamics computations suggest a complex interplay between magnetic exchange, electron delocalization and molecular vibrations. Yet, extensive experimental characterization of Cudaca by means of synchrotron x-ray diffraction, magnetization, specific heat and inelastic neutron scattering reveal that properties of the real material can be only partly explained by proposed theoretical models as the low temperature properties seem to be governed by a manifold of molecular configurations coexisting at high temperatures.



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