Dielectric properties of some MM'O{sub 4} and MTiM'O{sub 6} (M=Cr, Fe, Ga; M'=Nb, Ta, Sb) rutile-type oxides

• Published in: Journal of solid state chemistry 2010-06, Vol.183 (6)
• Main Authors: Mani, Rohini, Achary, S.N., Chakraborty, Keka R., Deshpande, S.K., Joy, Joby E., Nag, Abanti, Gopalakrishnan, J., Tyagi, A.K.
• Format: Article
• Language: English
• Subjects: AMBIENT TEMPERATURE; ANTIMONY COMPOUNDS; CHALCOGENIDES; CHROMIUM COMPOUNDS; COHERENT SCATTERING; CRYSTAL LATTICES; CRYSTAL STRUCTURE; DIELECTRIC MATERIALS; DIELECTRIC PROPERTIES; DIFFRACTION; ELECTRICAL PROPERTIES; FERROELECTRIC MATERIALS; GALLIUM COMPOUNDS; IRON COMPOUNDS; MATERIALS; MATERIALS SCIENCE; MINERALS; NEUTRON DIFFRACTION; NIOBIUM COMPOUNDS; OXIDE MINERALS; OXIDES; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; RADIOACTIVE MATERIALS; RADIOACTIVE MINERALS; REFRACTORY METAL COMPOUNDS; RUTILE; SCATTERING; TANTALUM COMPOUNDS; TEMPERATURE RANGE; TEMPERATURE RANGE 0013-0065 K; TETRAGONAL LATTICES; TRANSITION ELEMENT COMPOUNDS
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2010.04.022

We describe an investigation of the structure and dielectric properties of MM'O{sub 4} and MTiM'O{sub 6} rutile-type oxides for M=Cr, Fe, Ga and M'=Nb, Ta and Sb. All the oxides adopt a disordered rutile structure (P4{sub 2}/mnm) at ambient temperature. A partial ordered trirutile-type structure is confirmed for FeTaO{sub 4} from the low temperature (17 K) neutron diffraction studies. While both the MM'O{sub 4} oxides (CrTaO{sub 4} and FeTaO{sub 4}) investigated show a normal dielectric property MTiM'O{sub 6} oxides for M=Fe, Cr and M'=Nb/Ta/Sb display a distinct relaxor/relaxor-like response. Significantly the corresponding gallium analogs, GaTiNbO{sub 6} and GaTiTaO{sub 6}, do not show a relaxor response at T