Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
enabled [disable] Abstract
Number of results

Results found: 3

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
EN
The origin and thermal evolution of the EPR signals in SrCuO_2 ceramics are studied. It has been shown that the EPR signals observed in this ceramic material are due to contamination with other phases. The axial signal is due to SrCu(OH)_4·H_2O, which is a product of water reactions with SrCuO_2.
EN
Processes of SrCuO_2 and Sr_2CuO_3 ceramics decomposition induced by contact with water and carbon dioxide were studied by EPR. The dominant signals in the spectra were found to originate from Sr_2Cu(OH)_6 (for Sr_2CuO_3) and SrCu(OH)_4·H_2O (for SrCuO_2) compounds. The thermally induced conversion of SrCu(OH)_4·H_2O into Sr_2Cu(OH)_6 was analysed, and its product CuO was found to exist in the nanocrystalline form. The presence of CO_2, reacting with Sr(OH)_2, was shown to modify the decomposition process leading to the appearance of SrCu(OH)_4·H_2O, some hydroxycarbonates and Cu(OH)_2 on the surface of ceramics studied. At temperatures higher than 300ºC CuO reacts back with Sr(OH)_2. For the samples being in contact with atmospheric moisture this compound, deposited on a surface of SrCuO_2, decomposes to Sr_2Cu(OH)_6. The presence of the antiferromagnetic compounds Cu(OH)_2, CuO, and Cu_2[(OH)_2CO_3] in the samples can influence the results of magnetic measurements of the studied ceramics.
EN
Supertransferred hyperfine interactions between the Cu^{2+} unpaired electron and the ^{105}Pd nuclei in the Sr_2Pd_{0.99}Cu_{0.01}O_3 ceramic were studied by the EPR method. The spectrum of isolated -Pd-O-CuO_2-O-Pd- units (g_∥ = 2.280±0.001; g_⊥ = 2.040±0.001; A_∥(^{63}Cu) = 13 mT±0.1; A_∥(^{65}Cu) = 13.9 ±0.1 mT; A_⊥(^{63,65}Cu) = 0.0 mT) overlaps the signal from small groups of exchange coupled Cu^{2+} ions (g_∥ = 2.278±0.002; g_⊥ = 2.041±0.001). The isotropic contribution was shown to dominate in the Cu-Pd supertransferred interactions (A_∥(^{105}Pd) = A_⊥ (^{105}Pd) = 1 mT = a_{iso} Pd).
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.