Correlation of octahedral distortion with vibrational and electronic properties of LaFe1-Ti O3 nanoparticles

Strong Impact of Cr Doping on Structural and Magnetic Properties of Bi0.5La0.5Fe1−xCrxO3−δ

“…Firstly, Cr doping caused the disappearance of the tilt B 3g (2) mode but gave rise to the appearance of new lines at 252 cm À1 and 280 cm À1 , which can be assigned to the A g (4) and A g (6) modes, respectively. 45,48,49 This implies that the structural modification identified by NPD measurements is related to a change in the MO 6 octahedral tilting. Moreover, the modes observed at 468 cm À1 and 554 cm À1 as well as their secondorder counterparts were suppressed upon Cr doping.…”

“…44, the line at 325 cm À1 can be assigned to B 3g (2) tilt mode, whereas the two lines at 392 cm À1 and 468 cm À1 can be assigned to B 2g (3) and B 2g (2) bending modes, respectively. 45,48,49 The lines at 554 cm À1 and 619 cm À1 correspond to the A g (1) asymmetric stretching (AS) and the B 2g (1) symmetric stretching (SS) vibrations of FeO 6 octahedra, respectively. 45 It is important to note that the AS and SS modes are not allowed for orthorhombic non-Jahn-Teller (JT)-active systems.…”

Multi-scale chemo-mechanical evolution during crystallization of mixed conducting SrTi0.65Fe0.35O3−δ films and correlation to electrical conductivity

“…Increased distortions in the B-site polyhedra from rigid octahedral rotations have been associated with a decrease in the lattice parameter, 46 so the observed increase in alignment of neighboring polyhedra, or decrease in distortions, with crystallization could result in an expansion of the lattice. However, other distortions, such as changes in B-O bond length 45,46 or polyhedral connectivity, 47,48 can occur along with the polyhedral rotations. This, along with the change in coordination environment from oxidation, 49,50 convolutes the origin of crystallization-induced strain and results in complex structural changes.…”

Structural change from Pbnm to R3̅c phase with varying Fe/Mn content in (1-x) LaFeO3.xLaMnO3 solid solution leading to modifications in octahedral tilt and valence states

“…Nanocrystalline LFMO compositions of chemical formula LaFexMn1-xO3 (with x=0.0, 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875, 1.0, hereafter called LFO, LFMO12, LFMO25, LFMO37, LFMO50, LFMO62, LFMO75, LFMO87 and LMO, respectively), were synthesized using standard Pechini sol-gel method [48]. High purity precursors of La (Lanthanum (III) Oxide, Alfa Aesar, 99.9%), Fe (Iron (III) Nitrate Nona-hydrate, 98.0%) and Mn (Manganese (II) Carbonate, Alfa Aesar, 99.9%) were used for the synthesis of these materials.…”

“…A convergence criterion of 10-8 eV and 10-4 eVÅ -1 were chosen for total energy and ionic forces, respectively. The valence electron configurations of O, La, Fe, and Mn, as used in calculation for pseudopotentials generation are s 2 p 4 , s 2 p 6 d 1 s 2 , p 6 d 6 s 2 and p 6 d 5 s 2 respectively [48]. The phonon frequencies have been calculated using density functional perturbation theory (DFPT) [54].…”