F:Flammable;7440-16-6Relevant articles and documents
Nature of the Short Rh-Li Contact between Lithium and the Rhodium ω-Alkenyl Complex [Rh(CH2CMe2CH2CH═CH2)2]-
Liu, Sumeng,Smith, Brett A.,Kirkland, Justin K.,Vogiatzis, Konstantinos D.,Girolami, Gregory S.
, p. 8790 - 8801 (2021/06/28)
We describe the preparation of the cis-bis(η1,η2-2,2-dimethylpent-4-en-1-yl)rhodate(I) anion, cis-[Rh(CH2CMe2CH2CH═CH2)2]-, and the interaction of this species with Li+ both in solution and in the solid state. For the lithium(diethyl ether) salt [Li(Et2O)][Rh(CH2CMe2CH2CH═CH2)2], VT-NMR and 1H{7Li} NOE NMR studies in toluene-d8 show that the Li+ cation is in close proximity to the dz2 orbital of rhodium. In the solid-state structure of the lithium(12-crown-4) salt [Li(12-crown-4)2][Li{Rh(CH2CMe2CH2CH═CH2)2}2], one lithium atom is surrounded by two [Rh(CH2CMe2CH2CH═CH2)2]- anions, and in this assembly there are two unusually short Rh-Li distances of 2.48 ?. DFT calculations, natural energy decomposition, and ETS-NOCV analysis suggest that there is a weak dative interaction between the 4dz2 orbitals on the Rh centers and the 2pz orbital of the Li+ cation. The charge-transfer term between Rh and Li+ contributes only about the 1/5 of the total interaction energy, however, and the principal driving force for the proximity of Rh and Li in compounds 1 and 2 is that Li+ is electrostatically attracted to negative charges on the dialkylrhodiate anions.
Rational Synthesis for a Noble Metal Carbide
Wakisaka, Takuo,Kusada, Kohei,Wu, Dongshuang,Yamamoto, Tomokazu,Toriyama, Takaaki,Matsumura, Syo,Akiba, Hiroshi,Yamamuro, Osamu,Ikeda, Kazutaka,Otomo, Toshiya,Palina, Natalia,Chen, Yanna,Kumara, Loku S. R.,Song, Chulho,Sakata, Osami,Xie, Wei,Koyama, Michihisa,Kubota, Yoshiki,Kawaguchi, Shogo,Arevalo, Ryan L.,Aspera, Susan M.,Arguelles, Elvis F.,Nakanishi, Hiroshi,Kitagawa, Hiroshi
, p. 1247 - 1253 (2019/12/04)
Transition metal carbides have attractive physical and chemical properties that are much different from their parent metals. Particularly, noble metal carbides are expected to be promising materials for a variety of applications, particularly as efficient catalysts. However, noble metal carbides have rarely been obtained because carbide phases do not appear in noble metal-carbon phase diagrams and a reasonable synthesis method to make noble metal carbides has not yet been established. Here, we propose a new synthesis method for noble metal carbides and describe the first synthesis of rhodium carbide using tetracyanoethylene (TCNE). The rhodium carbide was synthesized without extreme conditions, such as the very high temperature and/or pressure typically required in conventional carbide syntheses. Moreover, we investigated the electronic structure and catalytic activity for the hydrogen evolution reaction (HER). We found that rhodium carbide has much higher catalytic activity for HER than pure Rh. Our study provides a feasible strategy to create new metal carbides to help advance the field of materials science.
Ice Melting to Release Reactants in Solution Syntheses
Wei, Hehe,Huang, Kai,Zhang, Le,Ge, Binghui,Wang, Dong,Lang, Jialiang,Ma, Jingyuan,Wang, Da,Zhang, Shuai,Li, Qunyang,Zhang, Ruoyu,Hussain, Naveed,Lei, Ming,Liu, Li-Min,Wu, Hui
supporting information, p. 3354 - 3359 (2018/02/21)
Aqueous solution syntheses are mostly based on mixing two solutions with different reactants. It is shown that freezing one solution and melting it in another solution provides a new interesting strategy to mix chemicals and to significantly change the reaction kinetics and thermodynamics. For example, a precursor solution containing a certain concentration of AgNO3 was frozen and dropped into a reductive NaBH4 solution at about 0 °C. The ultra-slow release of reactants was successfully achieved. An ice-melting process can be used to synthesize atomically dispersed metals, including cobalt, nickel, copper, rhodium, ruthenium, palladium, silver, osmium, iridium, platinum, and gold, which can be easily extended to other solution syntheses (such as precipitation, hydrolysis, and displacement reactions) and provide a generalized method to redesign the interphase reaction kinetics and ion diffusion in wet chemistry.
