Spectroscopic characterization of Ba2LnSnO5.5 materials: ceramic substrates for high Tc superconductors

Nanocrystals of a new complex perovskite dielectric Ba2TmSbO6

“…All these four bands merged into a single Gaussian profile indicating the similarity of bending/stretching frequencies of the SbO 6 and TmO 6 octahedra. Similar spectral pattern with two strong and well-defined IR bands in the 400-650 cm −1 region has been found in a number of Ba 2 L n MO 6 perovskite type materials [21][22][23][24]. The weak band centred at 1053 cm −1 is assigned to the symmetric stretching mode 1 (A 1g ) of SbO 6 (TmO 6 ) octahedra.…”

Development, characterization, sintering, dielectric and optical properties of NdBa2ZrO5·5 nanocrystals

“…Therefore, in the present case, the strong band from 400 cm −1 is involving the asymmetric bending mode, ν 4 (T 1u ) of the ZrO 6 octahedra whilst the other strong broad band from 550 cm −1 can be assigned to the asymmetric stretching mode, ν 3 (T 1u ) of the ZrO 6 octahedra. The same spectral pattern, with two strong and well defined IR bands in the 400-600 cm −1 region, has also been found in a great number of A 2 BB O 6 perovskite type materials and they were assigned in the same way (Corsmit et al 1972;Blasse and Corsmit 1973;Zheng et al 1998;Lavat et al 2001). Finally, the weak band from 864 cm −1 can be assigned to the originally IR inactive symmetric stretching mode, ν 1 (A 1g ) of the ZrO 6 octahedra, activated by symmetry lowering.…”

Dielectric Relaxation and Collective Vibrational Modes of Double‐Perovskites A2SmTaO6 (A = Ba, Sr and Ca)

“…The energy band at around 370 cm −1 involves the asymmetric bending mode of the TaO 6 octahedra while the other strong broad band at around 600 cm −1 can be assigned to the asymmetric stretching mode of the TaO 6 octahedra . The same spectral pattern, with two strong and well‐defined IR bands in the 400–650 cm −1 region, has also been found in a large number of A 2 B′B″O 6 DPO‐type materials . This broad nature of the observed vibrational bands is due to the occurrence of absorption peaks of both samarium and tantalum oxide at almost the same wave numbers.…”

“…23 The same spectral pattern, with two strong and well-defined IR bands in the 400-650 cm À1 region, has also been found in a large number of A 2 B 0 B″O 6 DPO-type materials. [24][25][26][27][28] This broad nature of the observed vibrational bands is due to the occurrence of absorption peaks of both samarium and tantalum oxide at almost the same wave numbers. Finally, the weak band at around 850 cm À1 can be assigned to the symmetric stretching mode of the TaO 6 octahedra.…”