DYNAMICS OF SOLITONS AND POLARONS IN QUASI-ONE-DIMENSIONAL HALOGEN-BRIDGED MIXED-VALENCE COMPOUNDS

通过光诱导吸收（PA）测量卤素桥接金属配合物（MX链；M=Pt和X=Cl， Br或I），研究了电子-晶格耦合和链间相互作用对一维peerls - hubbard体系间隙态的影响。在CDW振幅较小的配合物中，观察到三个PA带al， a2和b。对链间相互作用不敏感的PA带a1和a2被分配给极化子。CDW的链间耦合度降低导致了一个中间间隙带b，这是由带电孤子引起的，而在CDW振幅较大的配合物中，观察到两个PA带a和b具有较长的寿命。这些PA波段的光谱形状和激发曲线与al、a2和b波段有很大的不同。这些结果表明，间隙态的产生过程和稳定能量强烈依赖于电子-晶格相互作用的大小。

The effects of the electron-lattice coupling and the interchain interaction on the gap states in the one-dimensional Peierls-Hubbard system have been investigated by the photo-induced absorption (PA) measurements of the halogen-bridged metal complexes (the MX chains ; M=Pt and X=Cl, Br or I). In the complexes having small amplitude of CDW,three PA bands named al, a2, and b are observed. The PA bands a1 and a2, which are insensitive to the interchain interation, are assigned to polarons. The decrease of the interchain coupling of CDW leads to a midgap band b, which is attributable to charged-solitons, While, in the complexes having large amplitude of CDW,there are observed the two PA bands A and B having the long life time. Spectral shapes and excitation profiles of these PA bands are considerebly different from those of the al, a2, and b bands. These results suggestthat generation processes and stabilization energies of the gap states are strongly dependent on the magnitude of electron-lattice interactions.