Redox mechanisms and density of holes by XAS in the compensated series Bi[sub 2[minus]x]Pb[sub x]Sr[sub 2]Ca[sub 1[minus]x]Y[sub x]Cu[sub 2]O[sub 8+[delta]] ( 0 [le] x [le] 1)

Journal Article · Thu Jul 01 00:00:00 EDT 1993 · Journal of Solid State Chemistry; (United States)

DOI:https://doi.org/10.1006/jssc.1993.1199· OSTI ID:5851150

Merrien, N; Studer, F; Poullain, G; Michel, C ^[1]; Flank, A M; Lagarde, P; Fontaine, A ^[2]

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1. CRISMAT, Caen (France)
2. Universite de Paris-Sud, Orsay (France)

Bi[sub 2[minus]x]Pb[sub x]Sr[sub 2]Ca[sub 1[minus]x]Y[sub x]Cu[sub 2]O[sub 8+[delta]] (0 [le] x [le] 1) of structural type Bi(2212) is a very interesting solid solution since one is able to adjust the critical temperature over a large range of x by means of a mere formal exchange of charge between cations which do not belong to the essential [CuO[sub 2]][sub [infinity]] planes. X-ray absorption spectroscopy was performed at bismuth, lead, and copper L[sub 3]-edges on the Bi[sub 2[minus]x]Pb[sub x]Sr[sub 2]Ca[sub 1[minus]x]Y[sub x]Cu[sub 2]O[sub 8+[delta]] (0 [le] x [le] 1) solid solution in order to investigate the formal valence states of the elements and the correlation between hole density on the [CuO[sub 2]][sub [infinity]] planes and superconducting properties. It is shown that lead substitution does affect the role of the [BiO][sub [infinity]] planes which exchange electrons (holes) with the [CuO[sub 2]][sub [infinity]] planes. The decrease of the hole density in the [CuO[sub 2]][sub [infinity]] planes with increasing x has been correlated to the decrease of [Tc]'s, whereas the rapid decrease of the diamagnetic volume for 0.3 [le] x [le] 0.7 has been understood on the basis of a segregation between bismuth- and lead-rich phases. 37 refs., 11 figs., 1 tab.

• OSTI ID: 5851150
• Journal Information: Journal of Solid State Chemistry; (United States), Vol. 105:1; ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BISMUTH OXIDES
X-RAY SPECTROSCOPY
CALCIUM OXIDES
COPPER OXIDES
LEAD OXIDES
STRONTIUM OXIDES
YTTRIUM OXIDES
ABSORPTION SPECTROSCOPY
CATIONS
CRITICAL TEMPERATURE
HOLES
MAGNETIC SUSCEPTIBILITY
OXIDATION
REDUCTION
STOICHIOMETRY
SUPERCONDUCTORS
VALENCE
ALKALINE EARTH METAL COMPOUNDS
BISMUTH COMPOUNDS
CALCIUM COMPOUNDS
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL REACTIONS
COPPER COMPOUNDS
IONS
LEAD COMPOUNDS
MAGNETIC PROPERTIES
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SPECTROSCOPY
STRONTIUM COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
YTTRIUM COMPOUNDS
360207* - Ceramics
Cermets
& Refractories- Superconducting Properties- (1992-)