Photoemission electron-phonon coupling

The key to understand the anomalous behaviors in A vC,o is the electron-electron interaction, U, and the electron-phonon interaction, S. In A vCgo, the important interaction as U is the Coulomb repulsion between the flu electrons. The importance of U has been pointed out based on the results of the photoemission experiments [15]. Also, in AxC o, the important interaction as S is the coupling of the tlu electrons to the intramolecular phonons of the CRaman experiments [16], Nevertheless, a complete understanding of the anomalous behaviors in AxCgo has not been established yet. The reason is that the system with the orbital degree of freedom in which both U and S are important has not been known so far [17-20],... 

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