The synthesis of new geometrically frustrated layered systems has fueled experimental work and progress in building models of low-dimensional magnetism. Compounds with the structure of the francisite mineral, Cu₃Bi(SeO₃)₂O₂Cl, are quasi-two-dimensional antiferromagnets with a kagome-type lattice. With the dominant ferromagnetic interaction in the layer and a weak interlayer antiferromagnetic bond, the main non-collinear state of francisite is easily destroyed by an external magnetic field, which opens the possibility of reversible switching between states with the minimum and maximum possible magnetization. In the region of metamagnetic transition, multiferroelectric effects and broadband absorption of electromagnetic waves are observed. The implantation of rare-earth ions R into the Bi position is accompanied by spin-reorientation phase transitions in Cu₃R(SeO₃)₂O₂X compounds, where X=Cl, Br.

Keywords: francisite, low-dimensional and frustrated magnetism, metamagnetism, multiferroics PACS: 61.50.−f, 75.10.Jm, 75.25.-j (all) DOI: 10.3367/UFNe.2020.05.038773 URL: https://ufn.ru/en/articles/2021/4/b/ 000691278000002 2-s2.0-85110598764 2021PhyU...64..344M Citation: Markina M M, Berdonosov P S, Dolgikh V A, Zakharov K V, Kuznetsova E S, Vasil’ev A N "Francisites as new geometrically frustrated quasi-two-dimensional magnets" Phys. Usp. 64 344–356 (2021) BibTexBibNote ® (generic)BibNote ® (RIS)MedlineRefWorks Received: 17th, March 2020, revised: 4th, May 2020, accepted: 22nd, May 2020 Оригинал: Маркина М М, Бердоносов П С, Долгих В А, Захаров К В, Кузнецова Е С, Васильев А Н «Франциситы как новые геометрически фрустрированные квазидвумерные магнетики» УФН 191 358–371 (2021); DOI: 10.3367/UFNr.2020.05.038773