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1. Ferrimagnetism and Half-metallicity in Cr-substituted Mn _4–x Cr _x Al ₁₁

   https://doi.org/10.1088/1361-648X/add8d8  

   Noor, Md_Fahel_Bin; Law, Ka_Ming; Yasmin, Nusrat; Hauser, Adam_J; Besara, Tiglet (May 2025, Journal of Physics: Condensed Matter)

   Abstract Single crystals of disordered Mn_4–xCr_xAl₁₁have been synthesized via the flux method. EDS on several crystals of various sizes and shapes revealed an average molar ratio of 17:9:74 for Mn:Cr:Al, while X-ray diffraction on three different crystals yield compositions Mn_2.26Cr_1.74Al₁₁(Mn_4–xCr_xAl₁₁,x= 1.74), Mn_0.83Cr_3.17Al₁₁, and Mn_1.07Cr_2.93Al₁₁. This compound crystallizes in space groupP–1, isostructural with both Mn₄Al₁₁and Cr₄Al₁₁. Magnetic measurements on several crystals show that this disordered compound is ferrimagnetic with a low effective moment ofμ_eff≈1.012±0.004 μ_B/f.u. and a non-reachable transition temperature. DFT calculations display opening of a bandgap in the spin-up channel near the Fermi level with increasing Cr content, an indication of half-metallicity. 

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2. Electronic structure and magnetic exchange interactions of Cr-based van der Waals ferromagnets. A comparative study between CrBr ₃ and Cr ₂ Ge ₂ Te ₆

   https://doi.org/10.1039/D0TC02003F  

   O. Fumega, Adolfo; Blanco-Canosa, S.; Babu-Vasili, H.; Gargiani, P.; Li, Hongze; Zhou, Jian-Shi; Rivadulla, F.; Pardo, Victor (October 2020, Journal of Materials Chemistry C)

   null (Ed.)

   Low dimensional magnetism has been powerfully boosted as a promising candidate for numerous applications. The stability of the long-range magnetic order is directly dependent on the electronic structure and the relative strength of the competing magnetic exchange constants. Here, we report a comparative pressure-dependent theoretical and experimental study of the electronic structure and exchange interactions of two-dimensional ferromagnets CrBr 3 and Cr 2 Ge 2 Te 6 . While CrBr 3 is found to be a Mott–Hubbard-like insulator, Cr 2 Ge 2 Te 6 shows a charge-transfer character due to the broader character of the Te 5p bands at the Fermi level. This different electronic behaviour is responsible for the robust insulating state of CrBr 3 , in which the magnetic exchange constants evolve monotonically with pressure, and the proximity to a metal–insulator transition predicted for Cr 2 Ge 2 Te 6 , which causes a non-monotonic evolution of its magnetic ordering temperature. We provide a microscopic understanding for the pressure evolution of the magnetic properties of the two systems. 

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3. Solvothermal Synthesis of [Cr ₇ S ₈ (en) ₈ Cl ₂ ]Cl ₃  ⋅ 2H ₂ O with Magnetically Frustrated [Cr ₇ S ₈ ] ⁵⁺ Double‐Cubes**

   https://doi.org/10.1002/chem.202103761  

   Gamage, Eranga H.; Clark, Judith K.; Yazback, Maher; Cheng, Hai‐Ping; Shatruk, Michael; Kovnir, Kirill (December 2021, Chemistry – A European Journal)

   Abstract A novel transition metal chalcohalide [Cr₇S₈(en)₈Cl₂]Cl₃ ⋅ 2H₂O, with [Cr₇S₈]⁵⁺dicubane cationic clusters, has been synthesized by a low temperature solvothermal method, using dimethyl sulfoxide (DMSO) and ethylenediamine (en) solvents. Ethylenediamine ligand exhibits bi‐ and monodentate coordination modes; in the latter case ethylenediamine coordinates to Cr atoms of adjacent clusters, giving rise to a 2D polymeric structure. Although magnetic susceptibility shows no magnetic ordering down to 1.8 K, a highly negative Weiss constant,θ=−224(2) K, obtained from Curie‐Weiss fit of inverse susceptibility, suggests strong antiferromagnetic (AFM) interactions betweenS=3/2 Cr(III) centers. Due to the complexity of the system with (2S+1)⁷=16384 microstates from seven Cr³⁺centers, a simplified model with only two exchange constants was used for simulations. Density‐functional theory (DFT) calculations yielded the two exchange constants to beJ₁=−21.4 cm⁻¹andJ₂=−30.2 cm⁻¹, confirming competing AFM coupling between the shared Cr³⁺center and the peripheral Cr³⁺ions of the dicubane cluster. The best simulation of the experimental data was obtained withJ₁=−20.0 cm⁻¹andJ₂=−21.0 cm⁻¹, in agreement with the slightly stronger AFM exchange within the triangles of the peripheral Cr³⁺ions as compared to the AFM exchange between the central and peripheral Cr³⁺ions. This compound is proposed as a synthon towards magnetically frustrated systems assembled by linking dicubane transition metal‐chalcogenide clusters into polymeric networks. 

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4. Identification of Surface Structures in Pt ₃ Cr Intermetallic Nanocatalysts

   https://doi.org/10.1021/acs.chemmater.8b04774  

   LiBretto, Nicole J.; Yang, Ce; Ren, Yang; Zhang, Guanghui; Miller, Jeffrey T. (March 2019, Chemistry of Materials)
5. High Magnetic Anisotropy and Magnetocaloric Effects in Single-Crystal Cr ₂ Te ₃

   https://doi.org/10.1021/acsaelm.4c00009  

   Goswami, Anirban; Ng, Nicholas; Abeykoon, AM Milinda; Yakubu, Emmanuel; Guchhait, Samaresh (June 2024, ACS Applied Electronic Materials)