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《Physics letters. A》2020,384(26):126672
Ab initio density-functional theory calculations with spin polarization are performed to explore magnetic properties in zigzag green phosphorene nanoribbons (ZGPNRs) with no passivation or edge-saturated by H, OH and O chemical species. It is found that antiferromagnetic order at intra-edges is the most energetically favorable for the pristine and oxygen passivated ribbons, while H- or OH-saturated ZGPNRs show nonmagnetic order. It indicates that edge states arising from the unsaturated bonds are vital for the formation of the magnetic moment in the ZGPNRs. The magnitude of the edge magnetism in the pristine and O-saturated ZGPNRs is comparable to that in zigzag black phosphorene nanoribbons. Electronic band structures, spin densities and spd-orbital projected density of states for the studied pristine and O-passivated ZGPNRs are further analyzed to study their electronic properties. The magnetic and electronic properties discovered in the ZGPNRs may suggest potential applications in future spintronics and electronics. 相似文献
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Gas-phase 21Ne nuclear magnetic resonance spectra were measured at the natural abundance of 21Ne isotope for samples consisting of pressurized neon up to 60 bar at room temperature and applying the magnetic field of the strength B0 = 11.7574 T. It showed that the nuclear magnetic resonance frequency is linearly dependent on the density of gaseous neon. The resonance frequency was extrapolated to the zero-density point, and it permitted the determination of the 21Ne nuclear magnetic moment, μ(21Ne) = 0.6617774(10) μN. The present value of μ(21Ne) is not influenced by the bulk magnetic susceptibility of neon and interactions between neon atoms; therefore, it is more precise and reliable than the previous result obtained for μ(21Ne). 相似文献
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This paper presents objective priors for robust Bayesian estimation against outliers based on divergences. The minimum -divergence estimator is well-known to work well in estimation against heavy contamination. The robust Bayesian methods by using quasi-posterior distributions based on divergences have been also proposed in recent years. In the objective Bayesian framework, the selection of default prior distributions under such quasi-posterior distributions is an important problem. In this study, we provide some properties of reference and moment matching priors under the quasi-posterior distribution based on the -divergence. In particular, we show that the proposed priors are approximately robust under the condition on the contamination distribution without assuming any conditions on the contamination ratio. Some simulation studies are also presented. 相似文献
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Xi Su Zhiye Zhong Dr. Xiaoli Yan Dr. Ting Zhang Chuanzhe Wang Dr. Yi-Xuan Wang Prof. Gang Xu Prof. Long Chen 《Angewandte Chemie (International ed. in English)》2023,62(22):e202302645
As an emerging class of promising porous materials, the development of two-dimensional conductive metal organic frameworks (2D c-MOFs) is hampered by the few categories and tedious synthesis of the specific ligands. Herein, we developed a nonplanar hexahydroxyl-functionalized Salphen ligand (6OH-Salphen) through a facile two-step synthesis, which was further applied to construct layered 2D c-MOFs through in situ one pot synthesis based on the synergistic metal binding effect of the N2O2 pocket of Salphen. Interestingly, the C2v-symmetry of ligand endows Cu-Salphen-MOF with periodically heterogeneous pore structures. Benefitting from the higher metal density and shorter in-plane metal-metal distance, Cu-Salphen-MOF showcased excellent NO2 sensing performance with good sensitivity, selectivity and reversibility. The current work opens up a new avenue to construct 2D c-MOF directly from nonplanar ligands, which greatly simplifies the synthesis and provides new possibilities for preparing different topological 2D c-MOF based functional materials. 相似文献
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Lei Wang Man Zhang Ying‐Ying Jin Qing Lu Qi Fang 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(1):69-74
Three 1‐phenylindolin‐2‐one derivatives, namely 1‐phenylindolin‐2‐one, C14H11NO, (I), 5‐bromo‐1‐phenylindolin‐2‐one, C14H10BrNO, (II), and 5‐iodo‐1‐phenylindolin‐2‐one, C14H10INO, (III), have been synthesized and their structures determined. Compounds (I) and (II) crystallized in the centrosymmetric space groups Pbca and P21/c, respectively, while compound (III) crystallized in the polar space group Aea2. Density functional theory (DFT) calculations show that the molecular dipole moment gradually decreases in the order (I) > (II) > (III). The relatively smaller dipole moment of (III) and the larger non‐electrostatic intermolecular interactions may be the main reasons for the noncentrosymmetric and polar structure of (III). 相似文献