[CrE(PEt)]（E = S、Se、Te）簇分子中低激发态的实验和理论证据。

Experimental and theoretical evidence for low-lying excited states in [CrE(PEt)] (E = S, Se, Te) cluster molecules.

作者信息

Bügel Patrick, Krummenacher Ivo, Weigend Florian, Eichhöfer Andreas

机构信息

Institut für Nanotechnologie, Karlsruher Institut für Technologie (KIT), Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.

Institut für Anorganische Chemie, Universität Würzburg, 97074 Würzburg, Germany.

出版信息

Dalton Trans. 2022 Oct 4;51(38):14568-14580. doi: 10.1039/d2dt01690g.

DOI:10.1039/d2dt01690g

PMID:36074758

Abstract

Three [CrE(PEt)] cluster molecules with E = S, Se, and Te have been synthesized by reaction of stoichiometric mixtures of Cr(II) and Cr(III) metal salts with silylated chalcogen reagents E(SiMe) (E = S, Se, Te) in the presence of L = PEt = triethylphosphine. For the sulfide- and selenide-bridged clusters two crystallographic forms (trigonal 3̄ and triclinic 1̄), which differ in the presence of lattice solvent molecules, have been isolated. Structural data, optical spectra and quantum chemical calculations reveal the presence of low-lying excited states in [CrE(PEt)] (E = S, Se), which would help in rationalizing the non-vanishing magnetic moments at 2 K revealed by DC magnetic measurements and EPR spectroscopy. These findings are partially in contrast to a previous report by Saito and co-workers (S. Kamiguchi, H. Imoto, T. Saito, , 1998, , 6852-6857.), who postulated an incorporated hydrogen atom as the source of paramagnetism at low temperatures for the trigonal forms of [CrE(PEt)] (E = S, Se).

摘要

通过在配体(L = PEt =)三乙膦存在的情况下，使化学计量比的(Cr(II))和(Cr(III))金属盐混合物与硅烷基化的硫属试剂(E(SiMe))（(E = S)、(Se)、(Te)）反应，合成了三种([CrE(PEt)])簇分子，其中(E = S)、(Se)和(Te)。对于硫化物和硒化物桥连的簇，已经分离出两种晶体形式（三方晶系(\overline{3})和三斜晶系(\overline{1})），它们在晶格溶剂分子的存在上有所不同。结构数据、光谱和量子化学计算表明([CrE(PEt)])（(E = S)、(Se)）中存在低激发态，这有助于解释直流磁测量和电子顺磁共振光谱在(2K)时显示的非零磁矩。这些发现与Saito及其同事之前的报告（S. Kamiguchi、H. Imoto、T. Saito，，1998，，6852 - 6857.）部分相反，他们假设掺入的氢原子是三方形式的([CrE(PEt)])（(E = S)、(Se)）在低温下顺磁性的来源。