On the basis of the varying amplitude and patterns of the (19)F NMR chemical shift of C6F5X (X = F, Cl, Br, I) in the presence of chloride anions, bonding models of C6F5X·Cl(-) complexes were tentatively established, and the relevant binding constants were obtained. Interaction models were also simulated using computational chemistry. The theoretical computations were found to be highly consistent with the results of the experiments. The results show that C6F5Br/C6F5I and Cl(-) were prone to forming C-I/Br···Cl(-) σ-hole bonding complexes with the (19)F NMR signal shifting to higher fields, and the interaction strength of the C6F5I···Cl(-) σ-hole bond was larger than that of C6F5Br···Cl(-); C6F6/C6F5Cl and Cl(-) formed π-hole···Cl(-) bonding complexes with the signal shifting to lower fields, and the interaction strength of C6F6 was larger than that of C6F5Cl. The binding constant of the C6F5I···Cl(-) σ-hole bonding complex is 38.0 M(-1), which is nearly 165- to 345-fold larger than that of the other C6F5X·Cl(-) complexes. On the basis of the above results, solid phase extraction experiments were designed, and the results demonstrated the potential applicability of the C-I···Cl(-) σ-hole bond in separation science.
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http://dx.doi.org/10.1021/jp4097869 | DOI Listing |
Radiol Phys Technol
January 2025
Department of Radiology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
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Department of Psychological and Brain Sciences, Texas A&M University, 4235 TAMU, College Station, TX, 77843, USA.
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January 2025
Oak Ridge National Laboratory, Chemical Sciences Division, UNITED STATES OF AMERICA.
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Key Laboratory of Marine Genetic Resources, Third Institute of Oceanography, Ministry of Natural Resources of China; Key Laboratory of Marine Genetic Resources of Fujian Province, Xiamen 361005, PR China.
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View Article and Find Full Text PDFChem Commun (Camb)
January 2025
Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD 21045, USA.
Aqueous two-phase extraction (ATPE) is an effective and scalable liquid-phase processing method for purifying single species of single-wall carbon nanotubes (SWCNTs) from multiple species mixtures. Recent metrological developments have led to advances in the speed of identifying solution parameters leading to more efficient ATPE separations with greater fidelities. In this feature article, we review these developments and discuss their vast potential to further advance SWCNT separations science towards the optimization of production scale processes and the full realization of SWCNT-enabled technologies.
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