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1. Stabilization of NbTe ₃ , VTe ₃ , and TiTe ₃ via Nanotube Encapsulation

   https://doi.org/10.1021/jacs.0c10175  

   Stonemeyer, Scott; Cain, Jeffrey D.; Oh, Sehoon; Azizi, Amin; Elasha, Malik; Thiel, Markus; Song, Chengyu; Ercius, Peter; Cohen, Marvin L.; Zettl, Alex (March 2021, Journal of the American Chemical Society)

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2. Synthesis, crystal chemistry, and optical properties of two methylammonium silver halides: CH ₃ NH ₃ AgBr ₂ and CH ₃ NH ₃ Ag ₂ I ₃

   https://doi.org/10.1039/d1tc01737c  

   Gray, Matthew B.; Holzapfel, Noah P.; Liu, Tianyu; da Cruz Pinha Barbosa, Victor; Harvey, Nicholas P.; Woodward, Patrick M. (July 2021, Journal of Materials Chemistry C)

   Two novel ternary compounds from the pseudobinary CH3NH3X–AgX (X = Br, I) phase diagrams are reported. CH3NH3AgBr2 and CH3NH3Ag2I3 were synthesized via solid state sealed tube reactions and the crystal structures were determined through a combination of single crystal and synchrotron X-ray powder diffraction. Structurally, both compounds consist of one-dimensional ribbons built from silvercentered tetrahedra. The structure of CH3NH3AgBr2 possesses orthorhombic Pnma symmetry and is made up of zig-zag chains where each silver bromide tetrahedron shares two edges with neighboring tetrahedra. The tetrahedral coordination of silver is retained in CH3NH3Ag2I3, which has monoclinic P21/m symmetry, but the change in stoichiometry leads to a greater degree of edge-sharing connectivity within the silver iodide chains. With band gaps of 3.3 eV (CH3NH3Ag2I3) and 4.0 eV (CH3NH3AgBr2) the absorption onsets of the ternary phases are significantly blue shifted from the binary silver halides, AgBr and AgI, due in part to the decrease in electronic dimensionality. The compounds are stable for at least one month under ambient conditions and are thermally stable up to approximately 200 1C. Density functional theory calculations reveal very narrow valence bands and moderately disperse conduction bands with Ag 5s character. Bond valence calculations are used to analyze the hydrogen bonding between methylammonium cations and coordinatively unsaturated halide ions. The crystal chemistry of these compounds helps to explain the dearth of iodide double perovskites in the literature. 

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3. Tuning In-Plane Magnetic Anisotropy and Interfacial Exchange Coupling in Epitaxial La _2/3 Sr _1/3 CoO ₃ /La _2/3 Sr _1/3 MnO ₃ Heterostructures

   https://doi.org/10.1021/acsami.3c10376  

   Feng, Mingzhen; Ahlm, Nolan; Sasaki, Dayne Y.; Chiu, I-Ting; N’Diaye, Alpha T.; Shafer, Padraic; Klewe, Christoph; Mehta, Apurva; Takamura, Yayoi (November 2023, ACS Applied Materials & Interfaces)
4. Growth mode and strain effect on relaxor ferroelectric domains in epitaxial 0.67Pb(Mg _1/3 Nb _2/3 )O ₃ –0.33PbTiO ₃ /SrRuO ₃ heterostructures

   https://doi.org/10.1039/D0RA10107A  

   Belhadi, Jamal; Gabor, Urška; Uršič, Hana; Daneu, Nina; Kim, Jieun; Tian, Zishen; Koster, Gertjan; Martin, Lane W.; Spreitzer, Matjaž (January 2021, RSC Advances)

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   Controlling the growth of complex relaxor ferroelectric thin films and understanding the relationship between biaxial strain–structural domain characteristics are desirable for designing materials with a high electromechanical response. For this purpose, epitaxial thin films free of extended defects and secondary phases are urgently needed. Here, we used optimized growth parameters and target compositions to obtain epitaxial (40–45 nm) 0.67Pb(Mg 1/3 Nb 2/3 )O 3 –0.33PbTiO 3 /(20 nm) SrRuO 3 (PMN–33PT/SRO) heterostructures using pulsed-laser deposition (PLD) on singly terminated SrTiO 3 (STO) and ReScO 3 (RSO) substrates with Re = Dy, Tb, Gd, Sm, and Nd. In situ reflection high-energy electron diffraction (RHEED) and high-resolution X-ray diffraction (HR-XRD) analysis confirmed high-quality and single-phase thin films with smooth 2D surfaces. High-resolution scanning transmission electron microscopy (HR-STEM) revealed sharp interfaces and homogeneous strain further confirming the epitaxial cube-on-cube growth mode of the PMN–33PT/SRO heterostructures. The combined XRD reciprocal space maps (RSMs) and piezoresponse force microscopy (PFM) analysis revealed that the domain structure of the PMN–33PT heterostructures is sensitive to the applied compressive strain. From the RSM patterns, an evolution from a butterfly-shaped diffraction pattern for mildly strained PMN–33PT layers, which is evidence of stabilization of relaxor domains, to disc-shaped diffraction patterns for high compressive strains with a highly distorted tetragonal structure, is observed. The PFM amplitude and phase of the PMN–33PT thin films confirmed the relaxor-like for a strain state below ∼1.13%, while for higher compressive strain (∼1.9%) the irregularly shaped and poled ferroelectric domains were observed. Interestingly, the PFM phase hysteresis loops of the PMN–33PT heterostructures grown on the SSO substrates (strain state of ∼0.8%) exhibited an enhanced coercive field which is about two times larger than that of the thin films grown on GSO and NSO substrates. The obtained results show that epitaxial strain engineering could serve as an effective approach for tailoring and enhancing the functional properties in relaxor ferroelectrics. 

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5. Simulating Vapor–Liquid Equilibria of PH ₃ , AsH ₃ , and SbH ₃ from First Principles

   https://doi.org/10.1021/acs.jpcc.0c11495  

   Chen, Jingyi L.; Siepmann, J. Ilja (March 2021, The Journal of Physical Chemistry C)

   null (Ed.)