@article{3013698,
    title = "EPR study of Cu2+ ions in the Pr0.5RE0.5Ba2Cu3O6 + x compounds in tetragonal phase at low temperatures",
    author = "Guskos, N. and Likodimos, V. and Koufoudakis, A. and Bojanowski, B. and Typek, J. and Wabia, M.",
    journal = "Journal of Magnetism and Magnetic Materials",
    year = "1995",
    volume = "140-144",
    number = "PART 2",
    pages = "1319-1320",
    issn = "0304-8853",
    doi = "10.1016/0304-8853(94)01433-7",
    keywords = "Annealing;  Cooling;  Copper oxides;  Cryostats;  Crystal impurities;  Crystal symmetry;  Electron spectroscopy;  Ions;  Magnetic relaxation;  Paramagnetic resonance;  Phase transitions;  Spectrometers, Electron paramagnetic resonance spectra;  Exchange interaction;  Singlet triplet transitions;  Solid state reaction;  Tetragonal phase;  Zero field splitting parameter, Praseodymium compounds",
    abstract = "Powdered samples of the Pr0.5RE0.5Ba2Cu3O6 + x compounds, where RE Yb, Ho, Tm, Er, and Y, were investigated by the EPR technique at low temperatures in the range 2.8-20 K. In the EPR spectra of these non-superconducting materials in tetragonal phase, resonance lines arising from the exchange interaction of coupled pairs of divalent copper ions and Cu2+ in the tetragonal local crystal field symmetry were recorded. Apart from the usually observed ΔMs = 1 and ΔMs = 2 transitions for the CuCu system, rarely reported singlet-triplet transitions were detected as well. The exchange parameter J has roughly the same value of about 0.12 cm-1 for all investigated samples and the zero-field splitting parameter D is of the order of 0.013 cm-1. It is suggested that formation of Cu(1)OCu(2) copper coupled pairs is responsible for the observed EPR spectrum. © 1995."
}