Electronic structure of the quasi-one-dimensional halogen-bridged Ni complexes
Electronic structure of the quasi-one-dimensional halogen-bridged Ni complexes
复制标题
准一维卤桥Ni配合物的电子结构
DOI：
10.1103/physrevb.54.8438
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Yamashita
中科院分区：
文献类型：
--
作者：
Okamoto;Shimada;Oka;Chainani;Takahashi;Kitagawa;Mitani;Toriumi;Inoue;Manabe;Yamashita
用光谱学、X射线光电子能谱(XPS)和俄歇电子能谱研究了一维镍配合物[Ni(Chxn)2X]X2(X=Cl，Br；(Chxn)=1R，2R-环己二胺)和离散镍配合物[Ni X2([14]ane N4)]ClO4(X=Cl；Br；([14]ane N4)=1，4，8，11-四氮杂环十二烷)的电子结构.光谱表明，与含氯化合物相比，含溴化合物的能隙较小。用一个简单的X-Ni-X三聚体模型对光谱和Ni2pXP谱进行分析，得到了离散和一维Ni络合物的电荷转移能Δ和转移能T的定量估计。结合价态Xp谱对Ni的LVV俄歇能谱的分析表明，一维和离散的Ni络合物的平均在位d-d库仑能U约为5 eV，与二卤化镍的情况非常相似。结果表明，所合成的一维Ni络合物为CT绝缘体。根据Δ、T和U的估计参数值，讨论了一维Ni络合物与二卤化镍和一维铂络合物在电子结构上的差异。
The electronic structure of the one-dimensional Ni complexes,[Ni (chxn) 2 X] X 2 (X= Cl, Br;(chxn)= 1R, 2R-cyclohexanediamine), is studied together with the discrete Ni complexes,[Ni X 2 ([14] aneN 4)] ClO 4 (X= Cl; Br;([14] aneN 4)= 1, 4, 8, 11-tetraazacyclote tradecane), using optical spectroscopy, x-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy. The optical spectra show that the Br compounds have a smaller gap as compared with the Cl compounds. An analysis using a simple X-Ni-X trimer model on the optical spectra and the Ni 2p XP spectra yields quantitative estimates for the charge transfer (CT) energy Δ and the transfer energy T for discrete and one-dimensional Ni complexes. The analysis on the Ni LVV Auger spectra in conjunction with the valence XP spectra indicates that the average on-side d-d Coulomb energy U in the one-dimensional and discrete Ni complexes is about 5 eV, quite similar to the case of the Ni dihalides. The obtained results demonstrate that the one-dimensional Ni complexes are CT insulators. We discuss the differences in the electronic structures of the one-dimensional Ni complexes compared with the Ni dihalides and the one-dimensional Pt complexes on the basis of the estimated parameter values of Δ, T, and U.© 1996 The American Physical Society.