OK-edge and CuL23-edge XANES study on the concentration and distribution of holes in the(Pb2/

The oxidation states of copper and iron in mineral sulfides, and the oxides formed on initial exposure of chalcopyrite and bornite to air

“…The 530.1 eV value reported by Karppinen et al (2001) for CuO appears to be reliable and is in close agreement with the 530.2 eV obtained by Todd et al (2003b) for tenorite. Accordingly, the leading absorption peak energy of 530.2 eV for FeOOH and Fe 2 O 3 reported by Todd et al (2003b), rather than the value of 529.8 eV quoted earlier by Todd et al (2003a), has been adopted here.…”

XANES Study on the Generation and Distribution of Holes via Ca Substitution and O Doping in Cu(Ba0.8Sr0.2)2(Yb1−Ca )Cu2O6+

“…Each M m A 2 Q nÀ1 Cu n O m+2+2nÀd phase is denoted in an unambiguous way by M-m (A) 2 (Q) (n-1)n, though the shorter names, M-m2(n-1)n, are more commonly used (1). According to this general notation, the systematic name for the Cu(1)Ba 2 RCu(2) 2 O 7Àd or the socalled ''R-123'' phase is Cu-1 (Ba) 2 (R) 12 or Cu-1212. For an M m A 2 Q nÀ1 Cu n O m+2+2nÀd phase, the ''nominal average hole concentration'' in the superconductive CuO 2 plane(s) of the Q nÀ1 Cu n O 2n block is determined at a certain stoichiometry of the cations, M, A and Q, by the amount of oxygen in the M m O mÀd charge reservoir (1).…”

Oxygen nonstoichiometry and valence of copper in the Cu-1222 superconductor

“…(In the case of the HPO samples, O K-edge data were not considered due to Ag oxide inclusions in these samples in not welldefined amounts.) The pre-edge peak seen for all the samples about $528.1 eV is the well-known signature of hole states in the p-type doped CuO 2 planes in high-T c superconductors [20,[25][26][27][28]31,[34][35][36]. We can distinguish another pre-edge peak at $527.3 eV partly overlapping with this peak.…”

“…At the same time, no sign of an additional peak around 934 eV is seen that would indicate the presence of (two-fold coordinated) monovalent Cu species. (Note that such a feature is clearly observed for oxygen-deficient samples of the Cu-1212 [26,27] and (Pb 2/3 Cu 1/3 )-3212 [28] superconductors and also for the binary copper oxide Cu 2 O [29], all containing monovalent Cu in a linear coordination.) We analyzed the Cu L 3 -edge spectral features by fitting the intensities of the 931.2 and 932.7-eV peaks into a combination of Lorentzian and Gaussian functions after approximating the background to a straight line.…”