Larson James T, Wix Katelyn D, Chen Banghao, Latturner Susan E
Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida 32306, United States.
Inorg Chem. 2023 Aug 21;62(33):13277-13283. doi: 10.1021/acs.inorgchem.3c01511. Epub 2023 Aug 6.
Reactions of anthracene in Ln/T eutectic mixtures (Ln = La, Yb; T = Ni, Cu) have produced crystals of new complex lanthanide carbide hydride phases. The thermal decomposition of anthracene provides a source of both carbon and hydrogen. LaCH forms in space group with unit cell parameters = 7.2736(4) Å, = 3.7218(2) Å, and = 13.0727(7) Å. YbCH forms in space group -31 with unit cell parameters = 3.5659(4) Å and = 5.8000(8) Å, with a structure related to that of HoCF. The presence of hydride in interstitial sites is supported by the formation of different compounds in the absence of hydrogen and by comparison to known hydride structures. H nuclear magnetic resonance (NMR) spectra collected on LaCH show two unique hydride resonances, in agreement with the two available interstitial sites. Density of states calculations show that filling the tetrahedral sites in LaCH with hydrogen increases metallic behavior, while adding hydrogen into the tetrahedral sites in YbCH induces the formation of a band gap.
蒽在镧系/过渡金属共晶混合物（镧系元素 = 镧、镱；过渡金属 = 镍、铜）中的反应产生了新型镧系碳氢化物复合相的晶体。蒽的热分解提供了碳和氢的来源。LaCH形成于空间群 ，晶胞参数 = 7.2736(4) Å， = 3.7218(2) Å，以及 = 13.0727(7) Å。YbCH形成于空间群-31，晶胞参数 = 3.5659(4) Å以及 = 5.8000(8) Å，其结构与HoCF的结构相关。在没有氢的情况下形成不同化合物以及与已知氢化物结构进行比较，都支持了间隙位置存在氢化物。在LaCH上收集的氢核磁共振（NMR）光谱显示出两个独特的氢化物共振峰，这与两个可用的间隙位置一致。态密度计算表明，用氢填充LaCH中的四面体位置会增加金属特性，而向YbCH中的四面体位置添加氢会诱导带隙的形成。
