A combined diffraction (XRD, electron and neutron) and electrical study of Na3MoO3F3

New Layered Oxide-Fluoride Perovskites: KNaNbOF5 and KNaMO2F4 (M = Mo6+, W6+)

“…One well known example Na 3 MoO 3 F 3 , which crystallizes in the cryolite structure and has ordered oxide and fluoride ligands, displays ferroelectric-ferroelastic properties [3]. In this paper, we report a new class of A-site deficient oxyfluoride perovskites ABMO x F 6-x (where A = K + ; B = Na + ; x = 1, M = Nb 5+ ; x = 2, [19,20].…”

“…Perovskites with the general formula ABX 3 are some of the most studied structures owing to their many interesting properties including magnetism, ionic conductivity, and ferroelectricity [1][2][3]. Their structure and properties can be altered by substitution at either the A-or B-sites or creating either cation or anion vacancies.…”

“…Their structure and properties can be altered by substitution at either the A-or B-sites or creating either cation or anion vacancies. For example, ferromagnetism has been achieved with the complex perovskite AA' 3 B 4 O 12 , such as CaCu 3 Ge 4 O 12 [1], and ionic conductivity has been observed for the A-site deficient perovskites Li 3x La (2/3)-x □ 1/3-2x TiO 3 (0 < x < 0.16) [2].…”

Synthesis and Characterization of the Face-Sharing Bioctahedral [Mo2O6F3]3- Anion

“…A similar local ordering has been observed in Na 3 MoO 3 F 3 , in which oxides and fluorides are arranged in alternating planes: each Mo 6+ is coordinated to three oxides and three fluorides and is shifted closer to the fac-oriented oxides. 6 This oxide and fluoride ordering has been suggested for the entire family of elpasolite-related A 2 BMO 3 F 3 (A, B ) K + , Rb + , Cs + ; M ) Mo 6+ , W 6+ ) compounds. 7,8 Although [MO x F 6-x ] n-anions that contain a single metal cation have been closely examined, far less is known about polyoxofluoroanions.…”

“…It is important to note that the specific ligand ordering in isomer A is the only possible configuration of the [Mo 2 O 6 …”