Tables of Crystallographic Information

SSite composition fixed at 0.85 Tl + 0.15 Ca. However, site can also be modeled as containing only thallium with 11.3% vacancies. hSite composition fixed at 0.90 Ca + 0.10 Tl. 

Calculated atomic positions lattice parameters taken from reference 25. Atom displaced from la sites to 41 sites with quarter occupancy. SOccupancy factor refined to 0.94(1) atom/site. hSite composition fixed at 0.83 Ca + 0.17 Tl. 

Chemical Characterization of Oxide Superconductors by Analytical Electron Microscopy 

How can it arise that we seem unable to differentiate between the compositions, say, Bi2Sr2CaCu208 33 and BijSrj gyCa-Cu2Og (i.e. for a formal copper oxidation state of +2.33) Under 

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