Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

X-ray absorption of BaBiO sub 3 and superconducting BaBi sub 0. 25 Pb sub 0. 75 O sub 3

Journal Article · · Physical Review, B: Condensed Matter; (USA)
 [1];  [2];  [3];  [4];  [5]
  1. Xerox Palo Alto Research Center, Palo Alto, California 94304 (USA)
  2. Department of Physics, University of California, Santa Cruz, California 95064 (USA)
  3. Physics Department, Chalmers University of Technology, S-41296 Goeteborg, Sweden (SE)
  4. Department of Applied Physics, Stanford University, Stanford, California 94305 (USA)
  5. AT T Bell Laboratories, Murray Hill, New Jersey 07974 (USA)
X-ray-absorption studies of BaBiO{sub 3} and superconducting BaBi{sub 0.25}Pb{sub 0.75}O{sub 3} (Ba-Bi-Pb-O) did not show any structural transformations altering the gross-scale near-neighbor environment or the valence between 4 and 300 K. Two Bi-O distances, separated by about 0.17 A, could be distinguished for BaBiO{sub 3}. Also in Ba-Bi-Pb-O, there is a strong indication of two different Bi-O distances, separated by about 0.12 A, but only one Pb-O distance. The differing Bi-O separations may be connected with local spatial charge fluctuations. The valence states of the two differently located Bi atoms could not be conclusively determined from the absorption-edge shape, but the Bi and Pb near-edge structures for Ba-Bi-Pb-O are nearly identical. The Bi-O and Pb-O vibrational frequencies, considered important for superconductivity, could be estimated from the temperature dependence of the broadening of the nearest-neighbor distributions; they correspond to Einstein temperatures of about 500 K.
OSTI ID:
6837557
Journal Information:
Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 41:10; ISSN 0163-1829; ISSN PRBMD
Country of Publication:
United States
Language:
English