Synthesis, structure, and magnetic property of hexagonal perovskite Ba5Sn1.1Mn3.9O15

Influence of the synthesis route on the formation of 12R/10H-polytypes and their magnetic properties within the Ba(Ce,Mn)O3family

“…Similarly, the thermal treatment of the new composition 10H-Ba 5 Ce 0.83 Mn 4.17 O 15 produced the same behavior, for which a temperature-driven tetramer to trimer transformation was also observed. The complex magnetic properties inherent to manganese-based hexagonal perovskites have already been described in several works [11][12][13]27 and examined in our prior study on Ba 5 Ce 1.25 -Mn 3.75 O 15 . 14 In substance, it appears that systems that possess a significant number of Mn 3+ states within the mixed Mn 3+ -Mn 4+ valence generally show a Curie-Weiss behavior below room temperature followed by several kinds of antiferromagnetic-like …”

“…However, an interesting magnetic behavior has been reported by Yin et al12 in hexagonal perovskite-like oxides, where Ba 5 Sn 1.1 Mn 3.9 O 15 showed a spin glass transition at 7 K. Similarly, the 10H-Ba 5 Sb 1Àx Mn 4+x O 15Àd solid solution (0.24 o x o 0.36) presents a variety of magnetic properties that can be controlled by the x content of Mn in the corner-sharing Sb sites. 13 In the Ba-CeMn-O system, the recently reported 10H-Ba 5 Ce 1.25 Mn 3.75 O 15 polytype…”

Synthesis and crystal structure of a new hexagonal perovskite 7H-Ba7Li1.75Mn3.5O15.75with Mn4+/Mn5+charge distribution

“…In the structure of Ba 7 Li 1.75 Mn 3.5 O 15.75 , Mn 4+ and Li + cations are located in the octahedra forming 5 layers along the c axis of the unit cell. Considering that the average oxidation state of manganese is +4.5, it is probable that Mn 5+ cations occupy mainly the tetrahedral positions with one Mn-O distance of 1.606 (19) Å and the other three distances being 1.665(8) Å. The average Mn-O distance (1.65 Å) in the tetrahedra is somewhat smaller than the bond length in Sr 4 LiMn 2 O 9 (1.68 Å).…”

Molecule-like cluster magnetism and cationic order in the new hexagonal perovskite Ba4Sn1.1Mn2.9O12

“…Similar phenomena have been observed in the 10H Ba 5 Sn 1.1 Mn 3.9 O 15 polymorphs. 18 It should be noted about the distortion of outer MnO 6 octahedra in the trimers. The Mn at the M2 site shis toward the c-BaO 3 layers, forming three shorter Mn M2 -O2 bonds ($1.91 Å) and three longer Mn M2 -O1 bonds ($1.96 Å).…”

“…Many Mn-substituted BaM x Mn 1Àx O 3 systems have been investigated, for instance, with M ¼ Ca, 12,13 Ti, 14,15 In, 16,17 Sn, 18 Sb, 19 Fe, 20 Ru, 21,22 Ir, 23 and rare earth Ln. 24,25 This led to the uncovering of a range of M-cation (partially) ordered 12R perovskites Ba 4 Ti 2 Mn 2 O 12 , 14 Ba 4 InMn 3 O 11.5 , 16 Ba 4 REMn 3 O 12 (RE ¼ Ce and Pr), 24 Ba 4 YMn 3 O 11.5 , 26 and Ba 4 NbMn 3 O 12 .…”