Abstract
Ground state NMR spectra of Pr3+ in an axial host (LiYF4) have been obtained using an optical RF double resonance experiment in zero and low static magnetic fields. From the data, the authors obtained the spin Hamiltonian constants: gamma x/2 pi = gamma y/2 pi =+8.22+or-0.20 kHz G-1; gamma z/2 pi =+1.924+or-0.005 kHz G-1; D=+4737.2+or-0.2 kHz. The hyperfine interaction constant AJ for the ground state obtained from the measured value of gamma z/2 pi and the available electronic wavefunctions is 1093.8+or-8.8 MHz which is in excellent agreement with Bleaney's results. The dipolar interaction between Pr and F spins gives rise to a zero field structure of the Iz=+or-1/2 to +or-3/2 transition and to extra peaks in the low-field spectrum of the Iz=+or-1/2 to +or-3/2 and Iz=+or-3/2 to +or-u5/2 transitions. Determination of the spin-Hamiltonian constants including the dipolar constants from the observed data is discussed.