Document Type

Presentation

Publication Date

March 2012

Publication Title

National ACS Meeting

Disciplines

Chemistry

Abstract

We discuss bond resonance in high temperature layer superconducting cuprates, HTLSC alloys: (Bi1.7Pb0.3Sr2Can‐1CunO2n+4+δ)2,n=1‐9 called (2s:2:n‐1:n) prepared in Uzbekistan from melts in concentrated sun flux, followed by rapid cooling, SFQA technology that preserves melt tiling, Tc,n measured in Tiblisi, and local atomic enhanced synchrotron X‐ray diffraction, XRD near the Cu K‐edge at DOE National Laboratory SLAC‐SSRL. The SFQA alloys structure indexed in the ideal D17 4h Space Group indicates (n‐1) units: (CuO2)1/2/Ca/(CuO2)1/2 are intercalated at each end of the n=1 phase [(CuO2)1/2/SrO/Bi1.7Pb0.3O/Bi1.7Pb0.3O/SrO/(CuO2)1/2]2. Surface effects lead to different n‐phase mixing, and periodic lattice distortions, PLD, through bond resonance in crystal axes: 2(rCu+2+rO‐2)=4.2Å>a=3.815Å>(CuOorganic+(O=O‐O)/23/2)=3.2Å, c1=26.4Å, cn‐c1=1.64(n‐1)a, or δcn/(2a(n‐1))≈‐0.2. Local atomic bonds Cu‐Ca, Cu‐Sr, Cu‐O are detected by local atomic inelastic scattering. Tc,n related to bond resonance in the family predicts Tc,n⇒298K as n⇒50, if the superconducting skin depth is within a few μm.

Comments

Poster Presentation.

Included in

Chemistry Commons

Share

COinS