Fig. 2: Crystal field excitations and magnetic properties in Pr4+ oxides.
From: Chemical design of electronic and magnetic energy scales of tetravalent praseodymium materials
a, d Energy-dependent neutron-scattering intensity at low temperature integrated into the range 6 < Q < 7 Å−1 for several neutron energies and for 1-Pr (Sr2PrO4) and 0-Pr (Li8PrO6), respectively. b, e Magnetic susceptibility (χ(T)) and inverse susceptibility (χ(T)−1) data measured under μ0H = 3 T. Also plotted is a CF model and a Curie–Weiss analysis in the temperature range 4 < T < 40 K that yields \({\Theta }_{{{{{{{{\rm{CW}}}}}}}}}^{{{{{{{{\rm{1-Pr}}}}}}}}}=-7.52(2)\) K. The CF model calculations were carried out in Stevens operator formalism using the PYCRYSTALFIELD package58 with 14 \(\left|{m}_{l},{m}_{s}\right\rangle\) basis states to account for intermediate coupling. The inset shows macroscopic magnetic behavior under an applied field of μ0H = 0.1 T. 1-Pr exhibits an AFM order with a pronounced peak in χ(T) with no splitting between ZFC and FC. c Normalized IR transmission spectra as a function of applied magnetic field for 0-Pr. The blue color indicates the area with intense CF transitions, while yellow corresponds to the flat line. The experimental data were taken at 5 K and normalized to the average spectra as described in Methods. f Isothermal magnetization M(H) at T = 50 K for 0-Pr and 1-Pr plotted together with the CF model. T = 50 K was chosen so that 1-Pr is well above the ordering temperature and free from short-range correlations.
