Tuning of Charge Density Wave Strengths by Competition between Electron-Phonon Interaction of Pd(II)-Pd(IV) Mixed-Valence States and Electron Correlation of Ni(III) States in Quasi-One-Dimensional Bromo-Bridged Ni-Pd Mixed-Metal MX Chain Compounds Ni(1)(-)(x)()Pd(x)()(chxn)(2)Br(3).
A series of single crystals of quasi-one-dimensional bromo-bridged Ni-Pd mixed-metal MX chain compounds Ni(1)(-)(x)()Pd(x)()(chxn)(2)Br(3) (chxn = 1(R),2(R)-diaminocyclohexane) have been obtained by electrochemical oxidation methods of the mixed methanol solutions of parent Ni(II) complex [Ni(chxn)(2)]Br(2) and Pd(II) complex [Pd(chxn)(2)]Br(2) with various mixing ratios. To investigate the competition between the electron correlation of the Ni(III) states (or spin density wave states) and the electron-phonon interaction of the Pd(II)-Pd(IV) mixed-valence states (or charge density wave states) in the Ni-Pd mixed-metal compounds, IR, Raman, ESR, XP, and Auger spectra have been measured. The IR, resonance Raman, XP, and Auger spectra show that the Pd(II)-Pd(IV) mixed-valence states are influenced and gradually approach the Pd(III) states with the increase of the Ni(III) components. This means that in these compounds the electron-phonon interaction in the Pd(II)-Pd(IV) mixed-valence states is weakened with the strong electron correlation in the Ni(III) states.
Yamashita
Masahiro
M
Graduate School of Science & PRESTO (JST), Tokyo Metropolitan University, 1-1 Minamiohsawa, Hachioji, Tokyo 192-0397, Japan, Graduate School of Human Informatics, Nagoya University, Chikusa-ku, Nagoya 464-8601, Japan, Department of Applied Physics & PRESTO (JST), The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-8656, Japan, Japan Advanced Institute for Science and Technology, Ishikawa 923-1292, Japan, and Department of Applied Physics, Nagoya University, Chikusa-ku, Nagoya 464-8603, Japan.
Ishii
Tomohiko
T
Matsuzaka
Hiroyuki
H
Manabe
Toshio
T
Kawashima
Takuya
T
Okamoto
Hiroshi
H
Kitagawa
Hiroshi
H
Mitani
Tadaoki
T
Marumoto
Kazuhiro
K
Kuroda Si
Shin-ichi