Quadrupole and octupole deformation energy surfaces, low-energy excitation spectra and transition rates in fourteen isotopic chains: Xe, Ba, Ce, Nd, Sm, Gd, Rn, Ra, Th, U, Pu, Cm, Cf, and Fm, are systematically analyzed using a theoretical framework based on a quadrupole-octupole collective Hamiltonian (QOCH), with parameters determined by constrained reflection-asymmetric and axially-symmetric relativistic mean-field calculations. The microscopic QOCH model based on the PC-PK1 energy density functional and δ-interaction pairing is shown to accurately describe the empirical trend of low-energy quadrupole and octupole collective states, and predicted spectroscopic properties are consistent with recent microscopic calculations based on both relativistic and non-relativistic energy density functionals. Low-energy negative-parity bands, average octupole deformations, and transition rates show evidence for octupole collectivity in both mass regions, for which a microscopic mechanism is discussed in terms of evolution of single-nucleon orbitals with deformation.

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Recent demonstration of the interfacial Dzyaloshinskii-Moriya interaction (DMI) between a heavy metal and a magnetic insulator provides the possibility to manipulate chiral spin textures in the magnetic insulator for the extremely low power consumption devices. However, the origin and strength of the interfacial DMI remain in dispute in this system. We used the electrical transport measurements to determine the DMI strength to be ∼0.040 pJ/m at room temperature in Pt/Tm3Fe5O12 (TmIG) bilayers. The TmIG saturation magnetization and DMI strength exhibit different temperature dependences, which is attributed to the DMI being mainly contributed by Fe ions instead of Tm ions. With a Cu layer inserted between Pt and TmIG, the DMI strength is reduced to ∼0.012 pJ/m and the topological Hall effect vanishes, strongly suggesting that the Pt/TmIG interface has important contribution to the DMI.

Ketones serve as one of the most critical building blocks in organic synthesis, involving in numerous functional group transformations. Herein, we report an unprecedented photoredox/nickel metallaphotoredox-catalyzed decarboxylative acylation of common aliphatic acids with readily available aromatic and aliphatic thioesters. A wide range of structural diverse unsymmetrical arylalkyl and dialkyl ketones have been constructed in yields of up to 98% with this strategy. The protocol has excellent reaction selectivity and functional group compatibility, representing a significant step forward in ketone synthesis. The one-pot decarboxylative acylation at the gram scale from two different carboxylic acids and the late-stage application for the synthesis of complex ketones shows its synthetic robustness. Both mechanistic experiments and DFT calculations suggest that the decarboxylative acylation reaction tends to operate via an underdeveloped Ni(I)−Ni(II)−Ni(I)−Ni(III)-Ni(I) catalytic cycle.

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We report a thioacylation transfer reaction based on nickel-catalyzed C–C bond cleavage of thioesters with sp2-hybridized electrophiles. Aryl bromides, iodides, and alkenyl triflates can participate in thioester transfer reaction of aryl thioesters, affording a wide range of structurally diverse new thioesters in yields of up to 98% under mild reaction conditions. With this protocol, it is possible to construct alkenyl thioesters from the corresponding ketones through the generation of alkenyl triflates.

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The amidated peptides are an important class of biologically active compounds due to their unique biological properties and wide applications as potential peptide drugs and biomarkers. Despite the abundance of free amide motifs (Asn, Gln, and C-terminal amide) in native peptides, late-stage modification of the amide unit in naturally occurring peptides remains very rare because of the intrinsically weak nucleophilicity of amides and the interference of multiple competing nucleophilic residues, which generally lead to undesired side reactions. Herein, chemoselective arylation of amides in unprotected polypeptides has been developed under an air atmosphere to afford the N-aryl amide peptides bearing various functional motifs. Its success relies on the combination of gold catalysis and silver salt to differentiate the relative inert amide among a collection of reactive nucleophilic amino acid residues (e.g., −NH 2 , −OH, and −COOH), favoring the C−N bond coupling toward amides over other more nucleophilic groups. Experimental and DFT studies reveal a crucial role of the silver cation, which serves as a transient coordination mask of the more reactive reaction sites, overcoming the inherently low reactivity of amides. The excellent biocompatibility of this strategy has been applied to functionalize a wide range of peptide drugs and complex peptides. The application could be further extended to peptide labeling and peptide stapling.