Zone Center Phonons of Orthorhombic Perovskite YAlO3

Study of spin-phonon coupling and magnetic field induced spin reorientation in polycrystalline multiferroicGdFeO3

“…and c=0.768 nm, match well with literature 7 .Figure-1(b)show the room temperature Raman spectrum of the prepared GdFO sample along with the identified Raman modes. Experimentally observed Raman modes are assigned to the corresponding phonon mode with the help of lattice dynamical calculations reported earlier24,25 . According to the group theory, the irreducible representation for RF eO 3 compounds is given by Γ= 7A g +7B 1g + 5B 2g + 5B 3g + 8A 1u + 8B 1u + 10B 2u + 10B 3u in which 24 are Raman-active modes, 28 are infrared modes and 8 are inactive modes22,24,25 .…”

“…Experimentally observed Raman modes are assigned to the corresponding phonon mode with the help of lattice dynamical calculations reported earlier24,25 . According to the group theory, the irreducible representation for RF eO 3 compounds is given by Γ= 7A g +7B 1g + 5B 2g + 5B 3g + 8A 1u + 8B 1u + 10B 2u + 10B 3u in which 24 are Raman-active modes, 28 are infrared modes and 8 are inactive modes22,24,25 . The observed Raman modes of GdFO match closely with the recently reported Raman data of GdFO and also the other RF eO 3 compounds26,27 .…”

Orthorhombic YAlO3 – a novel many‐phonon SRS‐active crystal

“…, as well as Tables and ) that can be assigned to the respective normal vibrations manifested in its spontaneous Raman scattering spectra. Based on the knowledge achieved in the study of the vibronic properties of the title crystal (see, ) we were able to conclude that the observed SRS‐active phonons correspond to the following normal modes: ω SRS1 ≈ 335 cm −1 to the stretching mode A g – γ(AlO 6 ), ω SRS2 ≈ 265 cm −1 to the bending mode B 3g – δ as (AlO 6 ), ω SRS3 ≈ 148 cm −1 to translational mode A g – T’(YO 12 ), ω SRS4 ≈ 274 cm −1 to bending mode A g – δ s (AlO 6 ), ω SRS5 ≈ 552 cm −1 to stretching mode A g – ν s (AlO 6 ), ω SRS6 ≈ 195 cm −1 to translational mode A g – T’(YO 12 ) and ω SRS7 ≈ 400 cm −1 to stretching mode B 3g – ν as (AlO 6 ).…”

“…Its single‐crystal Raman studies were performed in . The assignment of the zone‐center phonons in these crystals was proposed in on the basis of the normal coordinate analysis using the Wilson‐GF matrix approach as well as in by use of lattice dynamical calculations. In the orthorhombic structure of YAlO 3 the aluminum atoms occupy the sites of the C i ‐symmetry at the centers of a distorted octahedron formed by the oxygen atoms.…”

Vacuum ultraviolet spectra and crystal field analysis ofYAlO3doped withNd3+andDuan1, Tanner2, Makhov3 et al. 2007Phys. Rev. B450310View full textAdd to dashboardCite

“…The highest energy gerade zone center phonon in YAP has the energy ϳ630 cm −1 . 8 We anticipated that suitably populated 4f N crystal field energy levels would exhibit luminescence in a dilute crystal if the gap below can be spanned by more than four quanta of this vibration ͑i.e., Ͼ2500 cm −1 ͒. From the energy level calculations for YAP: Nd 3+ , we therefore located the lowest crystal field levels of 2 F͑1͒ 7/2 ͑calculated at 64 338 cm −1 ͒, 2 G͑2͒ 9/2 ͑46 718 cm −1 ͒, 2 F͑2͒ 5/2 ͑37 939 cm −1 ͒, and 4 F 3/2 ͑11 421 cm −1 ͒ as the sole qualifying candidates below 65 000 cm −1 .…”