Ground states and thermally and optically excited states in quasi-one-dimensional halogen-bridged Pd/Ni mixed-metal complexes

从理论上研究了卤素桥联Pd/Ni混合金属络合物在不同混合比下的基态和热光激发态。主要结果如下：1.用DMRG方法很好地解释了混合比连续变化时的拉曼数据行为。2.利用DMRG方法，确定了电子关联效应是给出了从CDW到Mott绝缘体的状态突变。这一趋势与实验测量的金属价态是一致的。3.光诱导效应是双向的，即富CdW相的CDW到Mott绝缘体的转变和富Mott绝缘体相的Mott-绝缘体到CDW的转变。我们的最终估计是，一个电子和一个空穴的激发对平均产生20个位置的相变。

The ground state and thermally and optically excited states in halogen-bridged Pd/Ni mixed-metal complexes have been studied theoretically for various mixing ratios. The main results are:1.The Raman data behaviors when the mixing ratio is changed continuously are well explained by the present theory.2.Using the DMRG method, the effects of electron correlation is identified as giving a abrupt change of states from CDW to a Mott insulator. This tendency is consistent with the experimentally measured metal valencies.3.The photoinduced effects are identified as bi-directional ones, namely, CDW to Mott insulator transitions in a CDW-rich phase, and Mott-insulator to CDW transitions in a Mott-insulator-rich phase. Our final estimation is that one excited pair of an electron and a hole yields a phase conversion of 20 sites on the average.