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Organic–inorganic metal halides (OIMHs) have drawn considerable attention due to their remarkable optoelectronic properties and substantial promise for nonlinear optical applications. In this research, phenazine has been selected as the organic cation because of its π-conjugated feature. Three compounds, (C12H9N2)PbCl3, (C12H9N2)SbCl4, and (C12H9N2)2InBr4·Br, were synthesized. Initial space group assignments were centrosymmetric for (C12H9N2)PbCl3 and (C12H9N2)SbCl4. However, under 1550 nm laser excitation, (C12H9N2)PbCl3 and (C12H9N2)SbCl4 exhibited second harmonic generation intensities ∼1.7 times greater than that of the benchmark KH2PO4. Structural reevaluation ultimately confirmed non-centrosymmetric P1 and P21 space groups for (C12H9N2)PbCl3 and (C12H9N2)SbCl4, respectively. Upon excitation at 335 nm and 470 nm, (C12H9N2)PbCl3, (C12H9N2)SbCl4, and (C12H9N2)2InBr4·Br emit fluorescence at room temperature. (C12H9N2)2InBr4·Br exhibits reversible phase transitions, showing potential for phase change energy storage. Our research underscores the critical role of comprehensive experimental validation in determining the precise crystallographic space groups and reveals the extensive potential of OIMHs as versatile candidates for advanced optoelectronic applications. [ABSTRACT FROM AUTHOR]

Electric energy routers (EERs) can effectively deal with the energy management issues caused by the access of multi-sources and multi-loads. Different from the energy transmission form in the existing series architecture EER (SA-EER) for low-voltage distribution networks, a new series-parallel architecture EER (SPA-EER) has the advantages of high-power transmission capability and reactive power flexible operation. However, if controller parameters change beyond their critical stability boundaries, SPA-EER will produce slow- and fast-scale bifurcation behaviors, which are manifested as low- and high-frequency oscillations of port voltages or port currents in varying degrees. To avoid the system instability caused by controller parameter changes, how to discriminate the stability regions of controller parameters for SPA-EER is a key research content in this paper. To this end, the stroboscopic mapping discrete model of SPA-EER system is first established, and system bifurcation behaviors are analyzed based on bifurcation theory. Furthermore, the critical stability boundaries of controller parameters are discriminated by using Jacobian matrix, root locus and bifurcation diagram. After that, a time delay feedback control (TDFC) is employed to suppress system bifurcation behaviors. Finally, the correctness of bifurcation analysis and the effectiveness of TDFC are verified by a hardware-in-the-loop (HIL) experimental platform. [ABSTRACT FROM AUTHOR]

Efficient broadband emitting organic–inorganic metal hybrids (OIMHs) have attracted great attention recently as promising single‐component white light emitters. Here a new zero‐dimensional (0D) OIMH (C13H14N)2InCl5 (C13H14N+ = N‐methyldiphenylammonium) is reported, which features unique five‐coordinated [InCl5]2− trigonal bipyramid motif. For the first time, it is demonstrated that the trigonal bipyramid units in 0D OIMH can act as luminescence centers, showing blue emission under UV light. Remarkably, incorporating Sb3+ in [InCl5]2− trigonal bipyramids induces a new dual‐band emission at 540 and 735 nm resulting from the singlet and triplet self‐trapped excitons in [SbCl5]2−, leading to complete coverage of the entire visible spectrum. The resulting emissions in (C13H14N)2InCl5:Sb3+ are tunable from cold to warm white with the correlated color temperatures changing from 5574 to 3473 K and more importantly, an ultra‐high color rendering index (CRI) up to 96 being observed, which is comparable to the highest value in hybrid metal halides. A high photoluminescence quantum yield of 46.26% is simultaneously obtained in this system. This work demonstrates that the 0D OIMH with trigonal bipyramid motif is an excellent system for realizing the single‐component white light emission with both high efficiency and ultra‐high CRI. [ABSTRACT FROM AUTHOR]

The search for new materials with Dirac points has been a fascinating subject of condensed matter physics. Here we first report the growth and band structure of HfGe0.92Te single crystals featuring three different types of Dirac points. HfGe0.92Te crystallizes in a nonsymmorphic tetragonal space group P4/nmm (No. 129), having a square Ge-atom plane with vacancies of about 8%. Using angle-resolved photoemission spectroscopy (ARPES), the Dirac nodal line composed of conventional Dirac points vulnerable to spin-orbit coupling (SOC) is observed, accompanied by robust Dirac points protected by the nonsymmorphic symmetry against SOC and vacancies. In particular, spin-orbit Dirac points (SDPs) originating from the surface formed under significant SOC could exist based on ARPES and calculations. Quasi-two-dimensional (quasi-2D) characteristics are confirmed by angular-resolved magnetoresistance. HfGe0.92Te bulk crystals can be easily exfoliated to flakes with a thickness of approximately 5 nm for the quasi-2D nature. Thus, HfGe0.92Te provides a good platform to explore exotic topological phases or topological properties with three different types of Dirac points, which is a potential candidate to achieve novel 2D SDPs. [ABSTRACT FROM AUTHOR]

A one-dimensional (1D) halide double perovskite, (BA)10AgBi2Br19, is synthesized, which features 1D corner-sharing perovskite ribbons with a width of three octahedra. It is the first reported 1D derivative of a halide double perovskite, showing an unexpected narrow band gap (2.46 eV) due to the unique Br trimer in structure. [ABSTRACT FROM AUTHOR]