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Abstract Organofunctionalized tetranuclear clusters [(MIICl)2(VIVO)2{((HOCH2CH2)(H)N(CH2CH2O))(HN(CH2CH2O)2)}2] (1, M=Co,2: M=Zn) containing an unprecedented oxometallacyclic {M2V2Cl2N4O8} (M=Co, Zn) framework have been prepared by solvothermal reactions. The new oxo‐alkoxide compounds were fully characterized by spectroscopic methods, magnetic susceptibility measurement, DFT and ab initio computational methods, and complete single‐crystal X‐ray diffraction structure analysis. The isostructural clusters are formed of edge‐sharing octahedral {VO5N} and trigonal bipyramidal {MO3NCl} units. Diethanolamine ligates the bimetallic lacunary double cubane core of1and2in an unusual two‐mode fashion, unobserved previously. In the crystalline state, the clusters of1and2are joined by hydrogen bonds to form a three‐dimensional network structure. Magnetic susceptibility data indicate weakly antiferromagnetic interactions between the vanadium centers [Jiso(VIV−VIV)=−5.4(1); −3.9(2) cm−1], and inequivalent antiferromagnetic interactions between the cobalt and vanadium centers [Jiso(VIV−CoII)=−12.6 and −7.5 cm−1] contained in1.
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Medium‐Entropy Engineering of Magnetism in Layered Antiferromagnet Cu x Ni 2(1‐ x ) Cr x P 2 S 6
Abstract Antiferromagnetic van der Waals‐typeM2P2X6compounds provide a versatile material platform for studying 2D magnetism and relevant phenomena. Establishing ferromagnetism in 2D materials is technologically valuable. Though magnetism is generally tunable via a chemical way, it is challenging to induce ferromagnetism with isovalent chalcogen and bimetallic substitutions inM2P2X6. Here, we report co‐substitution of Cu1+and Cr3+for Ni2+in Ni2P2S6, creating CuxNi2(1‐x)CrxP2S6medium‐entropy alloys spanning a full substitution range (x= 0 to 1). Such substitution strategy leads to a unique evolution in crystal structure and magnetic phases that are distinct from traditional isovalent bimetallic doping, with Cu and Cr co‐substitution enhancing ferromagnetic correlations and generating a weak ferromagnetic phase in intermediate compositions. This aliovalent substitution strategy offers a universal approach for tuning layered magnetism in antiferromagnetic systems, which along with the potential for light‐matter interaction and high‐temperature ferroelectricity, can enable multifunctional device applications.
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- Award ID(s):
- 2238254
- PAR ID:
- 10641321
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Volume:
- 35
- Issue:
- 16
- ISSN:
- 1616-301X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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