Infrared and Transport Properties of the Layered Perovkite Related Oxide Ba5Nb4O15 and its Oxygen Deficient Phases

S. PAGOLA; N. E. MASSA; G. POLLA; G. LEYVA; R. E. CARBONIO

ELSEVIER SCIENCE BV

Año: 1994 vol. 235 p. 735 - 735

p style="TEXT-ALIGN: justify; LINE-HEIGHT: 200%; MARGIN: 0cm 0cm 0pt; TEXT-AUTOSPACE: ; mso-layout-grid-align: none" class="MsoNormal">Ba5Nb4O15-x, oxides were studied by infrared, electrical resistivity and thermogravimmetric analysis (TGA). FIR reflectivity, measurements reveal a strong ionic compound that has well defined features in groups that we assign to oxygen stretching, bending and lattice phonons splitted by the lower symmetry of this layered compound. For the sample with x = 0.56, oxygen vacancies do not affect phonon band profiles, indicating that carriers are not free enough to interact with longitudinal modes. Electrical resistivity vs. temperature measurements show that the oxygen deficient compounds, for low values of x, are small band gap semiconductors.