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1. A Metal-on-Metal Growth Approach to Metal–Metal Oxide Core–Shell Nanostructures with Plasmonic Properties

   https://doi.org/10.1021/acs.jpcc.0c03226  

   Crane, Cameron C. ; Manso, Ryan H. ; Li, Jun ; Benamara, Mourad ; Tao, Jing ; Zhu, Yimei ; Wang, Feng ; Chen, Jingyi ( July 2020 , The Journal of Physical Chemistry C)
2. Diverse bimetallic mechanisms emerging from transition metal Lewis acid/base pairs: development of co-catalysis with metal carbenes and metal carbonyl anions

   https://doi.org/10.1039/C7CC09675E  

   Mankad, Neal P. ( January 2018 , Chemical Communications)

   The rational development of catalytic reactions involving cooperative behavior between two catalytic reactive sites represents a frontier area of research from which novel reactivity and selectivity patterns emerge. Within this context, this Feature highlights the development of a cooperative system involving transition metal Lewis acid/base pairs. Bimetallic systems consisting of copper carbene Lewis acids and metal carbonyl anion Lewis bases, (NHC)Cu–[M CO ], are easily synthesized from readily available organometallic building blocks (NHC = N-heterocyclic carbene; [M CO ] − = metal carbonyl anion, e.g. [FeCp(CO) 2 ] − , [Mn(CO) 5 ] − , etc. ). Stoichiometric reactivity studies indicate that the dative Cu←M bonds in these systems are labile towards heterolysis under mild conditions, thus providing in situ access both to polar metal–metal bonds and to “frustrated” transition metal Lewis acid/base pairs as dictated by reaction conditions. Catalytic transformations ranging from C–C and C–B coupling reactions to hydrogenation and other reductions have been developed from both manifolds: bimetallic catalysis involving (a) binuclear intermediates engaging in cooperative bond activation and formation, and (b) orthogonal mononuclear intermediates that operate in either tandem or co-dependent manners. Preliminary indications point to the future emergence of novel reactivity and selectivity patterns as these new motifs undergo continued development, and additionally demonstrate that the relative matching of two reactive sites provides a method for controlling catalytic behavior. Collectively, these results highlight the fundamental importance of exploring unconventional catalytic paradigms. 

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3. METAL: The Metal Evolution, Transport, and Abundance in the Large Magellanic Cloud Hubble Program. III. Interstellar Depletions, Dust-to-Metal, and Dust-to-Gas Ratios versus Metallicity

   https://doi.org/10.3847/1538-4357/ac5248  

   Roman-Duval, Julia ; Jenkins, Edward B. ; Tchernyshyov, Kirill ; Clark, Christopher J. ; De Cia, Annalisa ; Gordon, Karl D. ; Hamanowicz, Aleksandra ; Lebouteiller, Vianney ; Rafelski, Marc ; Sandstrom, Karin ; et al ( March 2022 , The Astrophysical Journal)

   Abstract The metallicity and gas density dependence of interstellar depletions, the dust-to-gas (D/G), and dust-to-metal (D/M) ratios have important implications for how accurately we can trace the chemical enrichment of the universe, either by using FIR dust emission as a tracer of the ISM or by using spectroscopy of damped Ly α systems to measure chemical abundances over a wide range of redshifts. We collect and compare large samples of depletion measurements in the Milky Way (MW), Large Magellanic Cloud (LMC) ( Z = 0.5 Z ⊙ ), and Small Magellanic Cloud (SMC) ( Z = 0.2 Z ⊙ ). The relations between the depletions of different elements do not strongly vary between the three galaxies, implying that abundance ratios should trace depletions accurately down to 20% solar metallicity. From the depletions, we derive D/G and D/M. The D/G increases with density, consistent with the more efficient accretion of gas-phase metals onto dust grains in the denser ISM. For log N (H) > 21 cm −2 , the depletion of metallicity tracers (S, Zn) exceeds −0.5 dex, even at 20% solar metallicity. The gas fraction of metals increases from the MW to the LMC (factor 3) and SMC (factor 6), compensating for the reduction in total heavy element abundances and resulting in those three galaxies having the same neutral gas-phase metallicities. The D/G derived from depletions are respective factors of 2 (LMC) and 5 (SMC) higher than the D/G derived from FIR, 21 cm, and CO emission, likely due to the combined uncertainties on the dust FIR opacity and on the depletion of carbon and oxygen. 

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4. Metal–Metal (MM) Bond Distances and Bond Orders in Binuclear Metal Complexes of the First Row Transition Metals Titanium Through Zinc

   https://doi.org/10.1021/acs.chemrev.8b00297  

   Duncan Lyngdoh, Richard H. ; Schaefer, Henry F. ; King, R. Bruce ( December 2018 , Chemical Reviews)
5. Metal–Metal Bond Umpolung in Heterometallic Extended Metal Atom Chains

   https://doi.org/10.1021/acs.inorgchem.2c02118  

   Wheaton, Amelia M. ; Chipman, Jill A. ; Roy, Michael D. ; Berry, John. F. ( September 2022 , Inorganic Chemistry)