2 documents found, page 1 of 1
Espectroscopia vibracional e de impedância de A1-xA’xTaWO6.nH2O (A=H, Li, A’ = ...
Reis Júnior, Daniel Valim dosWe have performed the characterization of doped pyrochlore (H1−xAgxTaWO6.H2O) and trirutile (Hx Li1−x TaWO6 ) samples. Raman spectroscopy and infrared transmitance thechniques were used to investigate the structural properties of doped trirutile. The studies revealed that HxLi1−xTaWO6 samples belong to the tetragonal polar symmetry P421m(D32d). Raman spectroscopy studies were also used to identify the nature of...
Raman scattering and x-ray diffraction studies of polycrystalline CaCu3Ti4O12 u...
Reis Júnior, Daniel Valim dos; Souza Filho, Antônio Gomes de; Freire, Paulo de Tarso Cavalcante; Fagan, Solange Binotto; Ayala, Alejandro PedroWe report Raman scattering and x-ray diffraction studies of polycrystalline CaCu3Ti4O12 (CCTO) under high pressures. The pressure dependence of several Raman modes was investigated. No anomalies have been observed on the phonon spectra thereby indicating that the Th sIm 3¯d structure remains stable up to the maximum pressure s5.3 GPad we reached in this experiment. The pressure coefficients for the observed Ram...