Document Type

Presentation

Publication Date

October 2012

Publication Title

Almaden Institute

Disciplines

Chemistry

Abstract

High temperature layer superconducting cuprate (HTLSC) alloys: (Bi1.97Pb0.03Sr2Can-1CunO2n+4+δ)2 called (2s:2:n-1:n) have been grown from n-oxide stoichiometric melts in concentrated sun flux, followed by rapid cooling SFQA technology that preserves the melt tiling after annealing at 845±5oC**. Synchrotron XRD at the DOE SLAC-SSRL near the Cu K-edge has identified the mixing of n ≠ n’ alloys as observed by many in thin films last century. An ideal D17 4h Space Group structure obtains {an, bn, cn} = {3.815 Å, an+ubn, 2dP(n+3)+ucn} where dP is a perovskite sandwich, (CuO2)1/2|_Ca|(CuO2)1/2, thickness, and un are the amplitudes of periodic lattice distortions, PLD also observed last century*. Many electron interactions lead to covalent bonds indicated by 2(rCu+2+rO-2) =4.2Å > a = 3.82Å >d(CuO)+2-3/2d(O3)). Thus n-nano clusters grow n-1 perovskite sandwiches confined within a hard shell(CuO2)1/2|OSr|Bi1.97Pb0.03O|OBi1.97Pb0.03|SrO|(O2Cu)1/2. Disproportion reactions produce n’=Nn+3(N-1)>n clusters that are supported by n cluster pillars (fig. 1). The increase in the transition temperature to the superconducting state was determined by axial-torsional vibration measurements in transverse magnetic fields that obtain Tc⇒190K as n increases in ppm emergent regions***. n, n’ alloy mixtures identify Cu-Ca, Cu-Sr, Cu-O-Cu strong bond scattering. Example shows that enhancement at Q0=[11(n+3)]n=4,(n’=12)=2.53/Å is also detected at Q*=[1116]12, [1029]12 near Cu K-edge due to Cu-M bond back scattering that identify M=Ca, Sr, O, Cu (Table I, fig. 2).

Comments

This poster was presented at the Almaden Institute in 2012.

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