Lattice dynamics of CuGeO3: Inelastic neutron scattering and model calculations

Article

关键词: SPIN-PEIERLS TRANSITION;    PHONON COUPLING-CONSTANTS;    RAMAN-SCATTERING;    PHASE-DIAGRAM;    HEAT-CAPACITY;    FLUCTUATIONS;    SUPEREXCHANGE;    DIMERIZATION;    PRESSURE;    STATE;   

DOI  :  10.1103/PhysRevB.66.214417

来源: SCIE

【 摘 要 】

The lattice dynamics in CuGeO3 has been analyzed by the combination of inelastic neutron scattering studies and lattice-dynamical model calculations. We report on an almost complete set of dispersion curves along the three orthorhombic directions and along [101]. Some modes exhibit rather low phonon frequencies in relation either with the almost layered character of the crystal structure or with an instability of the CuO2 ribbons and GeO4 chains against twisting. The dispersion of branches associated with the modes directly involved in the spin-Peierls transition allows to explain the particular propagation vector of the structural distortion in the dimerized phase.

【 授权许可】

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