Bi2CoO2F4─A Polar, Ferrimagnetic Aurivillius Oxide-Fluoride

• Aurivillius oxides have been a research focus due to their ferroelectric properties, but by replacing oxide ions by fluoride, divalent magnetic cations can be introduced, giving Bi2MO2F4(M = Fe, Co, and Ni). Our combined experimental and computational study on Bi2CoO2F4 indicates a low-temperature polar structure of P21ab symmetry (analogous to ferroelectric Bi2WO6) and a ferrimagnetic ground state. These results highlight the potential of Aurivillius oxide-fluorides for multiferroic properties. Our research has also revealed some challenges associated with the reduced tendency for polar displacements in the more ionic fluoride-based systems. 

Subject headings

NATURVETENSKAP  -- Fysik (hsv//swe)

NATURAL SCIENCES  -- Physical Sciences (hsv//eng)

Keyword

Cobalt compounds

Ferrimagnetism

Ferroelectricity

Fluorine compounds

Ground state

Temperature

Tungsten compounds

Aurivillius

Co and Ni

Computational studies

Divalents

Ferrimagnetics

Ferroelectric property

Lows-temperatures

Oxide ions

Oxide-fluoride

Research focus

Bismuth compounds

Publication and Content Type

ref (subject category)

art (subject category)