X-ray Absorption Fine Structure Studies of Mn Coordination in Doped Perovskite SrTiO3
The coordination of Mn in doped SrTiO{sub 3} ceramics having nominal compositions SrTi{sub 0.98}Mn{sub 0.02}O{sub 3} and Sr{sub 0.98}Mn{sub 0.02}TiO{sub 3} was analyzed using x-ray absorption fine structure (XAFS) measurements. As expected, Mn{sup 4+} substitution for Ti{sup 4+} leads to Mn occupancy of the octahedral B-sites of ABO{sub 3} perovskite lattice with a Mn-O bond distance of 1.902 {angstrom} (compared to 1.953 {angstrom} for Ti-O) and no significant local distortions around the Mn atoms. In contrast, for the composition Sr{sub 0.98}Mn{sup 0.02}TiO{sub 3}, Mn segregates to both the A-sites (as Mn{sup 2+}) and the B-sites (predominantly as Mn{sup 4+}). Extended XAFS confirms strong ({approx} 0.77 {angstrom}) displacements of Mn{sup 2+} cations off the ideal A-site positions along <001> directions with a significant distortion of several coordination shells around the dopant atoms.
- Research Organization:
- Brookhaven National Lab. (BNL), Upton, NY (United States). National Synchrotron Light Source
- Sponsoring Organization:
- DOE - OFFICE OF SCIENCE
- DOE Contract Number:
- DE-AC02-98CH10886
- OSTI ID:
- 1019707
- Report Number(s):
- BNL-95553-2011-JA; APPLAB; TRN: US201115%%347
- Journal Information:
- Applied Physics Letters, Vol. 96, Issue 5; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
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