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Updated: Aug 21, 2026

Characterization of Nanocrystal Size Distribution using Raman Spectroscopy with a Multi-particle Phonon Confinement Model
Published on: August 22, 2015
Raman study of the orbital-phonon coupling in LaCoO3
A Ishikawa1, J Nohara, S Sugai
1Venture Business Laboratory, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601, Japan. a_ishikawa@nucc.cc.nagoya-u.ac.jp
Abstract:
The magnetic state in LaCoO3 changes from the low spin state (S=0) to the mixed state with a thermally excited intermediate spin state (IS) (S=1) above about 50 K. The partially filled e(g) orbital in the IS state has a nature of Jahn-Teller (JT) distortion. The cooperative JT distortion causes an orbital order. We found that all Raman active phonon modes are affected by the excitation of IS Co3+ ions. Especially, the JT vibration mode shows anomalous temperature dependence.
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