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Updated: Jan 1, 2026
Author Spotlight: Experimental Approaches for the Synthesis of Low-Valent Metal-Organic Frameworks from Multitopic Phosphine Linkers
Published on: May 12, 2023
Open-framework ammonium transition metal fluorophosphates with a Kagomé lattice network: synthesis, structure and
Jianhua Jiang1, Bei Zhu, Tianyu Zhu
1School of Environmental & Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, Jiangsu, China. m.f.lv@hotmail.com.
Abstract:
Two open-framework transition metal fluorophosphates (NH4)M3(PO3F)2(PO2F2)F2 (M = Mn and Co) have been synthesized under fluoride-rich hydrothermal conditions at 493 K. The structure consists of triplets of face-sharing trans-MO4F2 octahedra linked by PO3F groups to form 2D layers. These 2D layers with formula [M3(PO3F)2O2F2]3- in the ab plane are bridged by PO2F2 groups to generate a 3D open framework with 1D channels filled with ammonium cations. The XPS spectra suggested the existence of Mn(ii) and Co(ii) in the corresponding compounds. Further, the XPS F 1s spectra indicated that fluorine anions bridged both the M and P centres. The two compounds feature transition metal layers with a staircase Kagomé network. This topology promotes magnetic frustration, which exhibits a canted antiferromagnetic ground state (Tc = 8.0 K for Mn and Tc = 9.2 K for Co).
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