Paramagnetic susceptibilities, crystal field Stark energies and hyperfine properties of Eu3+ in europium trifluoromethanesulfonate nonahydrate

Hexagonal single crystals of europium trifluoromethanesulfonate nonahydrate (EuTFMS) have been prepared. The paramagnetic susceptibility perpendicular to the symmetry axis (c-axis, χ⊥) and the principal magnetic anisotropy (Δχ=χ||−χ⊥) were measured in the temperature range of 300-13 and 300-80 K, respectively. The paramagnetic susceptibility parallel to the c-axis (χ||) was calculated using the values of χ⊥ and Δχ. χ|| and χ⊥ increase slowly with decrease of temperature and below ∼93 K, χ⊥ is more or less constant. But χ|| levels off below ∼137 K. The calculated value of the effective magnetic moment (Peff) of Eu3+ in the crystalline environment of EuTFMS decreases with lowering of temperature. The Raman and Fourier transform infrared (FTIR) spectra of EuTFMS were recorded in the wavenumber range of 10-1800 and 370-6000 cm−1, respectively. A good theoretical simulation of the observed magnetic properties including the CF Stark energies of the ground term (7F) extracted from the Raman and FTIR spectra of Eu3+ in EuTFMS have been achieved using one electron crystal field (CF) analysis. The electronic specific heat and other relevant CF dependent hyperfine properties, viz, nuclear quadrupole splitting and hyperfine specific heat have been computed.