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Accurate identifying and in‐depth understanding of the defect sites in a working nanomaterial could hinge on establishing specific defect‐activity relationships. Yet, atomically precise coinage‐metal nanoclusters (NCs) possessing surface vacancy defects are scarce primarily owing to challenges in the synthesis and isolation of such defective NCs. Herein we report a mixed‐ligand strategy to synthesizing an intrinsically chiral and metal‐deficient copper hydride‐rich NC [Cu57H20(PET)36(TPP)4]+ (Cu57H20). Its total structure (including hydrides) and electronic structure are well established by combined experimental and computational results. Crystal structure reveals Cu57H20 features a cube‐like Cu8 kernel embedded in a corner‐missing metal‐ligand shell of Cu49(PET)36(TPP)4. Single Cu vacancy defect site occurs at one corner of the shell, evocative of mono‐lacunary polyoxometalates. Theoretical calculations demonstrate that the above‐mentioned point vacancy causes one surface hydride exposed as an interfacial capping μ3‐H−, which is accessible in chemical reaction, as proved by deuterated experiment. Moreover, Cu57H20 shows catalytic activity in the hydrogenation of nitroarene. The success of this work opens the way for the research on well‐defined chiral metal‐deficient Cu and other metal NCs, including exploring their application in asymmetrical catalysis. [ABSTRACT FROM AUTHOR]

Paleo‐Pacific subduction generated a prolonged active continental margin along the coast of the South China Block (SCB). A Triassic magmatic gap was argued to have occurred and was ascribed to flat‐slab subduction of an oceanic plateau. We study for the first time a >330‐m‐long core of typical arc volcanics dated at ca. 218 Ma from the Meiji Atoll in the southern South China Sea (SCS). Paleomagnetism suggests 4.1°± 1.5° of post‐eruption southward drift. These observations clearly support the existence of a Triassic arc in the SCB and imply that part of the arc later split off and drifted southward during the opening of the SCS in the Oligocene. Our results better constrain the lateral extent of the proposed flat‐slab subduction along the margin of the SCB. Moreover, we provide direct evidence of how the breakaway of ribbon continents operated in active continental margins, a recurrent scenario that has been invoked for Phanerozoic tectonics and continental growth throughout Asia. [ABSTRACT FROM AUTHOR]

The Nihewan Basin of China preserves one of the most important successions of Paleolithic archeological sites in Eurasia. Stratified archeological sites and mammalian fossils, first reported in the 1920s, continue to be recovered in large‐scale excavation projects. Here, we review key findings from archeological excavations in the Nihewan Basin ranging from ~1.66 Ma to 11.7 ka. We place particular emphasis on changes in stone tool technology over the long term. Though Pleistocene lithic industries from East Asia are often described as simple in character, re‐evaluation of the stone tool evidence from the Nihewan Basin demonstrates significant, though periodic, innovations and variability in manufacturing techniques through time, indicating adaptive and technological flexibility on the part of hominins. Synthesis of paleoenvironmental and archeological data indicate changes in hominin occupation frequency in the Nihewan Basin, with chronological gaps suggesting that continuous presence in high, seasonal latitudes was not possible prior to the Late Pleistocene. [ABSTRACT FROM AUTHOR]

ABSTRACT The Lesser Khingan Mountains of north-eastern China are heavily forested, making archaeological site identification difficult owing to poor ground surface visibility. Nevertheless, several prehistoric archaeological site discoveries have been made in recent years and a limited number of excavations have been initiated. One of the most important sites to emerge is Taoshan, which has yielded stratified stone tool assemblages dating from the Last Glacial Maximum (LGM) to the mid-Holocene. Pollen profiles indicate significant changes in vegetation, fluctuating from steppe conditions during the LGM to forested conditions in the Bølling-Allerød interstadial (B-A) and the mid-Holocene. The stone tool assemblages from Taoshan were primarily produced from varieties of volcanic tuff, rhyolite, hornfels and agate. Geological prospecting and petrological analyses were performed to document procurement sources and changes in raw material exploitation strategies. During the LGM, the predominant raw material was vitric tuff, available from a source ca. 5-10 km from Taoshan. In the B-A and mid-Holocene layers, emphasis was on the exploitation of raw materials in gravel bars, although stone tool reduction techniques and raw material preferences changed considerably during this time interval. Diachronic changes in raw materials and exploitation strategies correspond to changes in vegetation and human adaptations. [ABSTRACT FROM AUTHOR]

Three diiron and tetrairon azadithiolate complexes as models for the active site of [FeFe] hydrogenase were prepared. Reaction of complex Fe2(SCH2OH)2(CO)6 and NH2CH2CH2CH2OCH3 resulted in the diiron azadithiolate hexcarbonyl complex Fe2[(SCH2)2- NCH2CH2CH2OCH3](CO)6 (1) in moderate yield. Furthermore, treatment of complex 1 with mono phosphine ligand PPh3 and diphosphine ligand PH2PCH2CH2PPH2 in the presence of decarbonylation reagent Me3NO·2H2O yielded the phosphine-substituted azadithiolate complexes Fe2[(SCH2)2NCH2CH2CH2OCH3]CO)5(PPh3) (2) and {Fe2[(SCH2)2NCH2CH2CH2OCH3](CO)5}2(PH2PCH2CH2PPH2) (3) respectively. The new complexes 1-3 were fully characterized by elemental analysis, IR, ¹H, 13C, 31P NMR spectroscopy and X-ray crystallography. It is worthy to note that the crystallographic studies show the unusual difference of the methoxypropanyl substituent on the N atom of complexes 1 and 2, largely because of the affection of phosphine ligand PPh3. In addition, complex 1 was found to be a catalyst for H2 production under electrochemical condition. [ABSTRACT FROM AUTHOR]

Six new O‐alkyldithiophosphate nickel complexes with dcpf ligand, [(dcpf)Ni(S2P{O}OR)] (dcpf = 1,1′‐bis (dicyclohexylphosphino)ferrocene, R = CH3 (1), CH3CH2 (2), Ph (3), 4‐MeC6H4 (4), PhCH2 (5) and PhCH2CH2 (6)), have been synthesized by the treatment of dcpf with ((RO)2PS2)2Ni in satisfactory yields. These complexes were characterized by elemental analysis, spectroscopy (FTIR, UV–vis, 1H, 13C, and 31P NMR), thermogravimetric analysis and single crystal X‐ray diffraction. The nickel atom in 1, 2·CH2Cl2, 3·CH2Cl2, 4·2CH2Cl2·THF, and 2(5)·hexane adopts a slightly distorted square‐planar coordination environment finished by two phosphorus atoms of dcpf ligand and two sulfur atoms of O‐alkyldithiophosphate ligand. Furthermore, the electrochemical properties for complexes 1–6 were also investigated by cyclic voltammetry. With the addition of 120 mM trifluoroacetic acid (TFA), the turnover frequency (TOF) values for 1–6 are estimated to be 1243.83, 1046.54, 1331.71, 2545.29, 1899.03, and 1191.37 s−1, with the overpotential (η) values of 0.62, 0.58, 0.71, 0.67, 0.60, and 0.56 V, respectively. The result of electrochemical studies indicates that all complexes can be used as efficient molecular eletrocatalysts for the reduction of protons to hydrogen in the presence of TFA in MeCN. [ABSTRACT FROM AUTHOR]