Karbalaei, Sana; Franke, Alicja; Zahl, Achim; Pokkuluri, P Raj; Beyers, Ronald J; Ivanović-Burmazović, Ivana; Goldsmith, Christian R
(, Chemical Communications)
A highly air- and water-stable Fe(ii) complex with a fluorinated ligand has a strong19F MRI signal but is a poorT1-weighted1H MRI contrast agent. Upon oxidation by H2O2, the19F MRI signal decays as the relaxivity for1H MRI markedly improves.
Yan, Pei-Gen; Babb, James F
(, The Astrophysical Journal)
Abstract We calculate cross sections for fine-structure transitions of Ne+, Ar+, Ne2+, and Ar2+in collisions with atomic hydrogen by using quantum-mechanical methods. Relaxation rate coefficients are calculated for temperatures up to 10,000 K. The temperature-dependent critical densities for the relaxation of Ne+, Ar+, Ne2+, and Ar2+in collisions with H have been determined and compared to the critical densities for collisions with electrons. The present calculations will be useful for studies utilizing the infrared lines [Neii] 12.8, [Neiii] 15.6, [Neiii] 36.0, [Arii] 6.99, [Ariii] 8.99, and [Ariii] 21.8μm as diagnostics of, for example, planetary nebulae and star formation.
Gilbert-Bass, Kito; Stennett, Cary R.; Grotjahn, Robin; Ziller, Joseph W.; Furche, Filipp; Evans, William J.
(, Chemical Communications)
To expand the range of donor atoms known to stabilize 4fn5d1Ln(ii) ions beyond C, N, and O first row main group donor atoms, the Ln(iii) terphenylthiolate iodides, LnIII(SAriPr6)2I (AriPr6= C6H3-2,6-(C6H2-2,4,6-iPr3)2, Ln = La, Nd) were reduced to LnII(SAriPr6)2complexes.
Abstract A fundamental understanding of the enantiospecific interactions between chiral adsorbates and understanding of their interactions with chiral surfaces is key to unlocking the origins of enantiospecific surface chemistry. Herein, the adsorption and decomposition of the amino acid proline (Pro) have been studied on the achiral Cu(110) and Cu(111) surfaces and on the chiral Cu(643)R&Ssurfaces. Isotopically labelled 1‐13C‐l‐Pro has been used to probe the Pro decomposition mechanism and to allow mass spectrometric discrimination ofd‐Pro and 1‐13C‐l‐Pro when adsorbed as mixtures. On the Cu(111) surface, X‐ray photoelectron spectroscopy reveals that Pro adsorbs as an anionic species in the monolayer. On the chiral Cu(643)R&Ssurface, adsorbed Pro enantiomers decompose with non‐enantiospecific kinetics. However, the decomposition kinetics were found to be different on the terraces versus the kinked steps. Exposure of the chiral Cu(643)R&Ssurfaces to a racemic gas phase mixture ofd‐Pro and 1‐13C‐l‐Pro resulted in the adsorption of a racemic mixture; i.e., adsorption is not enantiospecific. However, exposure to non‐racemic mixtures ofd‐Pro and 1‐13C‐l‐Pro resulted in amplification of enantiomeric excess on the surface, indicative of homochiral aggregation of adsorbed Pro. During co‐adsorption, this amplification is observed even at very low coverages, quite distinct from the behavior of other amino acids, which begin to exhibit homochiral aggregation only after reaching monolayer coverages. The equilibrium adsorption ofd‐Pro and 1‐13C‐l‐Pro mixtures on achiral Cu(110) did not display any aggregation, consistent with prior scanning tunneling microscopy (STM) observations ofdl‐Pro/Cu(110). This demonstrates convergence between findings from equilibrium adsorption methods and STM experiments and corroborates formation of a 2D random solid solution.
Han, Jian, Tan, Liming, Wan, Yanjun, Li, Gang, and Anderson, Stephen N. C(sp 3 )–H oxidation and chlorination catalysed by a bioinspired pincer iron( iii ) complex. Retrieved from https://par.nsf.gov/biblio/10472080. Dalton Transactions 51.31 Web. doi:10.1039/D2DT02005J.
Han, Jian, Tan, Liming, Wan, Yanjun, Li, Gang, & Anderson, Stephen N. C(sp 3 )–H oxidation and chlorination catalysed by a bioinspired pincer iron( iii ) complex. Dalton Transactions, 51 (31). Retrieved from https://par.nsf.gov/biblio/10472080. https://doi.org/10.1039/D2DT02005J
Han, Jian, Tan, Liming, Wan, Yanjun, Li, Gang, and Anderson, Stephen N.
"C(sp 3 )–H oxidation and chlorination catalysed by a bioinspired pincer iron( iii ) complex". Dalton Transactions 51 (31). Country unknown/Code not available: Royal Society of Chemistry. https://doi.org/10.1039/D2DT02005J.https://par.nsf.gov/biblio/10472080.
@article{osti_10472080,
place = {Country unknown/Code not available},
title = {C(sp 3 )–H oxidation and chlorination catalysed by a bioinspired pincer iron( iii ) complex},
url = {https://par.nsf.gov/biblio/10472080},
DOI = {10.1039/D2DT02005J},
abstractNote = {A pincer iron(iii) catalyst for the oxidation and chlorination of C(sp3)–H bonds was developed.},
journal = {Dalton Transactions},
volume = {51},
number = {31},
publisher = {Royal Society of Chemistry},
author = {Han, Jian and Tan, Liming and Wan, Yanjun and Li, Gang and Anderson, Stephen N.},
}
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