Chemical bonding in and electronic structure of lithium and magnesium rhodium hydrides are studied theoretically using DFT methods. For Li3RhH4 with planar complex RhH4 structural units, Crystal Orbital Hamilton Populations reveal significant Rh−Rh interactions within infinite one-dimensional ∞ 1 [RhH4] stacks in addition to strong rhodium−hydrogen bonding. These metal−metal interactions are considerably weaker in the hypothetical, heavier homologue Na3RhH4. Both compounds are small-band gap semiconductors. The electronic structures of Li3RhH6 and Na3RhH6 with rhodium surrounded octahedrally by hydrogen, on the other hand, are compatible with a classical complex hydride model according to the limiting ionic formula (M+)3[RhH6]3− without any metal−metal interaction between the 18-electron hydridorhodate complexes. In MgRhH, building blocks of the composition (RhH2)4 are formed with strong rhodium−hydrogen and significant rhodium−rhodium bonding (bond lengths of 298 pm within Rh4 squares). These units are linked together to infinite two-dimensional layers ∞ 2 [(RhH2/2)4] via common hydrogen atoms. Li3RhH4 and MgRhH are accordingly examples for border cases of chemical bonding where the classical picture of hydridometalate complexes in complex hydrides is not sufficient to properly describe the chemical bonding situation.
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http://dx.doi.org/10.1021/ic402687p | DOI Listing |
Lab Chip
January 2025
Department of Life Science and Technology, Tokyo Institute of Technology, Nagatsuta 4259, Midori-ku, Yokohama 226-8501, Japan.
DNA methylation is a crucial epigenetic modification used as a biomarker for early cancer progression. However, existing methods for DNA methylation analysis are complex, time-consuming, and prone to DNA degradation. This work demonstrates selective capture of unmethylated DNAs using ZnO nanowires without chemical or biological modifications, thereby concentrating methylated DNA, particularly those with high methylation levels that can predict cancer risk.
View Article and Find Full Text PDFJ Org Chem
January 2025
College of Chemistry and Chemical Engineering, Jishou University, Jishou 416000, People's Republic of China.
A copper-catalyzed domino addition/cyclization reaction was developed to synthesize novel benzoselenazole-linked 1,2,3-triazole and tetracyclic fused 12-benzo[4,5]selenazole[2,3-]quinazolin-12-one derivatives from isoselenocyanates. This domino reaction efficiently constructed multiple new chemical bonds in a single step, forming either four (one C-Se and three C-) or three (one C-Se and two C-) bonds. The reaction offers several key advantages, including mild conditions, broad substrate compatibility, and straightforward and safe operation.
View Article and Find Full Text PDFJ Phys Chem B
January 2025
Key Laboratory for Ecological Metallurgy of Multimetallic Mineral (Ministry of Education), School of Metallurgy, Northeastern University, Shenyang, Liaoning 110819, China.
This study employs first-principles molecular dynamics (FPMD) simulations combined with the Voronoi tessellation method to explore the microstructure, transport properties, electronic properties, and Raman spectra of the NaF-AlF-CaF/LiF/KF systems with varying cryolite ratios, additive types, and concentrations. The results indicate that Na, Ca, Li, and K exist in a free state in the molten salts, while Al forms complex ion groups in the form of [AlF] with F, and free F also exists in the molten salts. In the NaF-AlF-CaF system, the average Al-F distance is slightly shorter than that in the other two systems, while the Al-F coordination number is higher in NaF-AlF-LiF.
View Article and Find Full Text PDFNanomaterials (Basel)
January 2025
Institute of Materials Science & Devices, School of Materials Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
Carbon catalysts have shown promise as an alternative to the currently available energy-intensive approaches for nitrogen fixation (NF) to urea, NH, or related nitrogenous compounds. The primary challenges for NF are the natural inertia of nitrogenous molecules and the competitive hydrogen evolution reaction (HER). Recently, carbon-based materials have made significant progress due to their tunable electronic structure and ease of defect formation.
View Article and Find Full Text PDFACS Nano
January 2025
Department of Thoracic Surgery, Shanghai Pulmonary Hospital, School of Medicine, Tongji University, Shanghai 200433, China.
For idiopathic pulmonary fibrosis (IPF), interleukin 11 (IL-11) is a pivotal cytokine that stimulates the transformation of fibroblasts into myofibroblasts, thus accelerating the progression of pulmonary fibrosis. Here, we develop an innovative inhalable small interfering RNA (siRNA) delivery system termed PEI-GBZA, which demonstrates impressive efficiency in loading siIL-11 targeting IL-11 (siIL-11) and substantially suppresses the differentiation of fibroblasts into myofibroblasts and epithelial-mesenchymal transition (EMT), reduces neutrophil and macrophage recruitment, and ultimately relieves the established fibrotic lesions in the IPF model. PEI-GBZA is prepared by modifying low-molecular-weight polyethylenimine (PEI) with 4-guanidinobenzoic acid (GBZA).
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