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Updated: May 30, 2026
Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Structural and vibrational properties of K(3)Fe(MoO(4))(2)(Mo(2)O(7))-a novel layered molybdate
M Maczka1, A Pietraszko, W Paraguassu
1Institute of Low Temperature and Structure Research, Polish Academy of Sciences, PO Box 1410, 50-950 Wrocław 2, Poland.
Abstract:
The new compound K(3)Fe(MoO(4))(2)(Mo(2)O(7)) was synthesized and characterized by a single-crystal x-ray structure determination, and IR and Raman spectroscopic studies. The crystal structure at room temperature and ambient pressure is monoclinic, space group C 2/c, with the unit cell dimensions a = 32.885(7), b = 5.7220(11), c = 15.852(3) Å, β = 91.11°, Z = 8. The FeO(6) octahedra are joined by corners with MoO(4)(2-) tetrahedra and Mo(2)O(7)(2-) units. Some of the K(+) ions form layers in the b × c-plane. The origin of various Raman and IR vibrational modes is discussed. These results indicate that a clear energy gap exists between the stretching and remaining modes. High-pressure Raman scattering studies were also performed. These studies showed the onset of two reversible first-order phase transitions near 1.2 and 7.4 GPa, which are associated with strong distortion of the MoO(4)(2-) and Mo(2)O(7)(2-) units.
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