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1. A review of band structure and material properties of transparent conducting and semiconducting oxides: Ga ₂ O ₃ , Al ₂ O ₃ , In ₂ O ₃ , ZnO, SnO ₂ , CdO, NiO, CuO, and Sc ₂ O ₃

   https://doi.org/10.1063/5.0078037  

   Spencer, Joseph A.; Mock, Alyssa L.; Jacobs, Alan G.; Schubert, Mathias; Zhang, Yuhao; Tadjer, Marko J. (March 2022, Applied Physics Reviews)

   This Review highlights basic and transition metal conducting and semiconducting oxides. We discuss their material and electronic properties with an emphasis on the crystal, electronic, and band structures. The goal of this Review is to present a current compilation of material properties and to summarize possible uses and advantages in device applications. We discuss Ga 2 O 3 , Al 2 O 3 , In 2 O 3 , SnO 2 , ZnO, CdO, NiO, CuO, and Sc 2 O 3 . We outline the crystal structure of the oxides, and we present lattice parameters of the stable phases and a discussion of the metastable polymorphs. We highlight electrical properties such as bandgap energy, carrier mobility, effective carrier masses, dielectric constants, and electrical breakdown field. Based on literature availability, we review the temperature dependence of properties such as bandgap energy and carrier mobility among the oxides. Infrared and Raman modes are presented and discussed for each oxide providing insight into the phonon properties. The phonon properties also provide an explanation as to why some of the oxide parameters experience limitations due to phonon scattering such as carrier mobility. Thermal properties of interest include the coefficient of thermal expansion, Debye temperature, thermal diffusivity, specific heat, and thermal conductivity. Anisotropy is evident in the non-cubic oxides, and its impact on bandgap energy, carrier mobility, thermal conductivity, coefficient of thermal expansion, phonon modes, and carrier effective mass is discussed. Alloys, such as AlGaO, InGaO, (Al x In y Ga 1− x− y ) 2 O 3 , ZnGa 2 O 4 , ITO, and ScGaO, were included where relevant as they have the potential to allow for the improvement and alteration of certain properties. This Review provides a fundamental material perspective on the application space of semiconducting oxide-based devices in a variety of electronic and optoelectronic applications. 

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2. Antiferromagnetic Ordering in A One‐Dimensional Organic Copper Chloride Hybrid Insulator

   https://doi.org/10.1002/anie.202412759  

   Islam, Md Sazedul; Comstock, Andrew; Hua, Zhenqi; Thapa, Puja; He, Yufang; Ben‐Akacha, Azza; Liu, He; Manny, Tarannuma Ferdous; Viera, Jarek; Lin, Xinsong; et al (November 2024, Angewandte Chemie International Edition)

   Abstract Low dimensional (LD) organic metal halide hybrids (OMHHs) have recently emerged as new generation functional materials with exceptional structural and property tunability. Despite the remarkable advances in the development of LD OMHHs, optical properties have been the major functionality extensively investigated for most of LD OMHHs developed to date, while other properties, such as magnetic and electronic properties, remain significantly under‐explored. Here, we report for the first time the characterization of the magnetic and electronic properties of a 1D OMHH, organic‐copper (II) chloride hybrid (C₈H₂₂N₂)Cu₂Cl₆. Owing to the antiferromagnetic coupling between Cu atoms through chloride bridges in 1D [Cu₂Cl₆²⁻]_∞chains, (C₈H₂₂N₂)Cu₂Cl₆is found to exhibit antiferromagnetic ordering with a Néel temperature of 24 K. The two‐terminal (2T) electrical measurement on a (C₈H₂₂N₂)Cu₂Cl₆single crystal reveals its insulating nature. This work shows the potential of LD OMHHs as a highly tunable quantum material platform for spintronics. 

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3. Evidence for Topological States and a Lifshitz Transition in Metastable 2 M ‐WSe ₂

   https://doi.org/10.1002/adfm.202420356  

   He, Yangchen; Strasser, Alex; Hagopian, Nicholas; Bierman, Brenna; Ma, Hongrui; Fox, Carter; Li, Zizhong; Pederson, Nicholas; Taniguchi, Takashi; Watanabe, Kenji; et al (March 2025, Advanced Functional Materials)

   Abstract In recent years,T_dtransition metal dichalcogenides have been heavily explored for their type‐II Weyl topology, gate‐tunable superconductivity, and nontrivial edge states in the monolayer limit. Here, the Fermi surface characteristics and fundamental transport properties of similarly structured 2M‐WSe₂bulk single crystals are investigated. The measurements of the angular dependent Shubnikov–de Haas oscillations, with support from first‐principles calculations, reveal multiple three‐ and two‐dimensional Fermi pockets, one of which exhibits a nontrivial Berry's phase. In addition, it is shown that the electronic properties of 2M‐WSe₂are similar to those of orthorhombic MoTe₂and WTe₂, having a single dominant carrier type at high temperatures that evolves into coexisting electron and hole pockets with near compensation at temperatures below 100 K, suggesting the existence of a Lifshitz transition. Altogether, the observations provide evidence towards the topologically nontrivial electronic properties of 2M‐WSe₂and motivate further investigation on the topological properties of 2Mtransition metal dichalcogenides in the atomically thin limit. 

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4. Towards accurate prediction for laser-coolable molecules: relativistic coupled-cluster calculations for yttrium monoxide and prospects for improving its laser cooling efficiencies

   https://doi.org/10.1039/D0CP04608F  

   Zhang, Chaoqun; Korslund, Hannah; Wu, Yewei; Ding, Shiqian; Cheng, Lan (November 2020, Physical Chemistry Chemical Physics)

   null (Ed.)

   Benchmark relativistic coupled-cluster calculations for yttrium monoxide (YO) with accurate treatment of relativistic and electron correlation effects are reported. The spin–orbit mixing of 2 Π and 2 Δ is found to be an order of magnitude smaller than previously reported in the literature. Together with the measurement of the lifetime of the A′ 2 Δ 3/2 state, it implies an enhanced capability of a narrow-line cooling scheme to bring YO to sub-recoil temperature. The computed electronic transition properties also support a four-photon scheme to close the leakage of the A 2 Π 1/2 ↔ X 2 Σ 1/2 + cycle through the A′ 2 Δ 3/2 state by repumping the A′ 2 Δ 3/2 state to the B 2 Σ 1/2 + state, which subsequently decays back to X 2 Σ 1/2 + . Relativistic coupled-cluster methods, capable of providing accurate spectroscopic parameters that characterize the local potential curves and hence of providing accurate Franck–Condon factors, appear to be promising candidates for accurate calculation of properties for laser-coolable molecules. 

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5. Trifluoromethylation of 2D Transition Metal Dichalcogenides: A Mild Functionalization and Tunable p‐Type Doping Method

   https://doi.org/10.1002/anie.202403494  

   Kerwin, Brendan; Liu, Stephanie E; Sadhukhan, Tumpa; Dasgupta, Anushka; Jones, Leighton O; López‐Arteaga, Rafael; Zeng, Thomas T; Facchetti, Antonio; Schatz, George C; Hersam, Mark C; et al (May 2024, Angewandte Chemie International Edition)

   Abstract Chemical modification is a powerful strategy for tuning the electronic properties of 2D semiconductors. Here we report the electrophilic trifluoromethylation of 2D WSe₂and MoS₂under mild conditions using the reagent trifluoromethyl thianthrenium triflate (TTT). Chemical characterization and density functional theory calculations reveal that the trifluoromethyl groups bind covalently to surface chalcogen atoms as well as oxygen substitution sites. Trifluoromethylation induces p‐type doping in the underlying 2D material, enabling the modulation of charge transport and optical emission properties in WSe₂. This work introduces a versatile and efficient method for tailoring the optical and electronic properties of 2D transition metal dichalcogenides. 

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