在具有高热稳定性和导电性的钯-氯链状配合物中存在一种不寻常的钯(III)氧化态。

An unusual Pd(III) oxidation state in the Pd-Cl chain complex with high thermal stability and electrical conductivity.

作者信息

Mian Mohammad Rasel, Wakizaka Masanori, Yoshida Takefumi, Iguchi Hiroaki, Takaishi Shinya, Afrin Unjila, Miyamoto Tatsuya, Okamoto Hiroshi, Tanaka Hisaaki, Kuroda Shin-Ichi, Breedlove Brian K, Yamashita Masahiro

机构信息

Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan.

Department of Advanced Material Science, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561, Japan.

出版信息

Dalton Trans. 2021 Feb 9;50(5):1614-1619. doi: 10.1039/d0dt03848b.

DOI:10.1039/d0dt03848b

PMID:33332512

Abstract

The Pd(iii) oxidation state is unusual and unstable since it strongly tends to disproportionate. We synthesized the quasi-one-dimensional (1D) halogen-bridged Pd(iii)-Cl complex [Pd(dabdOH)2Cl]Cl2 (1-Cl; dabdOH = (2S,3S)-2,3-diaminobutane-1,4-diol) with multiple hydrogen bonds. From single-crystal X-ray diffraction, the bridging Cl- ions were located at the midpoint of the Pd-Cl-Pd moieties in the 1D chains, indicating that the Pd ions are in a Pd(iii) average valence (AV) state. Moreover, bright spots for the Pd(iii) dz2 orbitals in the upper Hubbard band above the Fermi level were observed every ∼5 Å using scanning tunnelling microscopy. These results clearly indicate that the Pd ions are in a Pd(iii) AV state in 1-Cl. In addition, 1-Cl has the highest thermal stability (470 K) among the Pd(iii) complexes reported and the highest electrical conductivity (0.6 S cm-1 at 300 K) among the 1D Pd-Cl chains reported so far.

摘要

钯（III）氧化态并不常见且不稳定，因为它极易发生歧化反应。我们合成了具有多个氢键的准一维（1D）卤素桥连钯（III）-氯配合物[Pd(dabdOH)₂Cl]Cl₂（1-Cl；dabdOH = (2S,3S)-2,3-二氨基丁烷-1,4-二醇）。通过单晶X射线衍射，桥连Cl⁻离子位于一维链中Pd-Cl-Pd部分的中点，这表明钯离子处于钯（III）平均价态（AV）。此外，使用扫描隧道显微镜在费米能级以上的上哈伯德带中每隔约5 Å观察到钯（III）dz²轨道的亮点。这些结果清楚地表明，1-Cl中的钯离子处于钯（III）AV态。此外，1-Cl在已报道的钯（III）配合物中具有最高的热稳定性（470 K），在迄今为止报道的一维Pd-Cl链中具有最高的电导率（300 K时为0.6 S cm⁻¹）。