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Soliton excitations in halogen-bridged mixed-valence binuclear metal complexes

Shoji Yamamoto·Masanori Ichioka
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Abstract

Motivated by recent stimulative observations in halogen (X)-bridged binuclear transition-metal (M) complexes, which are referred to as MMX chains, we study solitons in a one-dimensional three-quarter-filled charge-density-wave system with both intrasite and intersite electron-lattice couplings. Two distinct ground states of MMX chains are reproduced and the soliton excitations on them are compared. In the weak-coupling region, all the solitons are degenerate to each other and are uniquely scaled by the band gap, whereas in the strong-coupling region, they behave differently deviating from the scenario in the continuum limit. The soliton masses are calculated and compared with those for conventional mononuclear MX chains.

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Shoji Yamamoto, Masanori Ichioka. 2001-10-24. Soliton excitations in halogen-bridged mixed-valence binuclear metal complexes. https://doi.org/10.1143/jpsj.71.189

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