Linewidth narrowing in the epr spectra of Gd3+ impurity ions due to the spin-lattice relaxation of lanthanide Kramers' host ions

The use of the electron paramagnetic resonance of Gd3+ impurity ions and infrared spectra to study the phase transitions in NH4Ce(SO4)2∙4H2O single crystals

“…The linewidth will be due to contributions from the dipolar interaction between Gd3+ spins and Gd3+ and Ce3+ spins. The dipolar field due to the Ce3+ ions experienced by the Gd3+ ions is due to exchange interaction between Ce3+ ions and produces "spinlattice relaxation" narrowing (26,29). It is most probable that each Gd3+ ion in ACST single crystals is surrounded by paramagnetic Ce3+ ions since the concentration of the Gd3+ impurity ions was -0.5%.…”

“…This was first proposed by Mitsuma (28) who suggested that the fast relaxation of the host ions can randomly modulate the dipolar and exchange interaction between paramagnetic host and impurity.ions, resulting in the spin-lattice relaxation narrowing. Malhotra et al (26,29,30) have shown that the conditions for the spin-lattice relaxation narrowing are satisfied in the lanthanide Kramers' host ions a t temperatures -300 K. The epr impurity ion linewidths provide information about the host r , when the spin-lattice relaxation narrowing is effective (26,(28)(29)(30) ABinlP is the impurity linewidth, Scff is the host ion effective spin, 17 is the host paramagnetic ion density, gcff is the effective host ion g-value, and Ei are the ground state splittings of the host Kramers' ion doublets. The 2F5/2 ground state of Ce3+ ions will split in the presence of a nearly axial crystalline electric field to give three Kramers' doublets (E,, i = 1, 2, 3).…”

Characterization of olivine single crystals grown by the micro‐pulling‐down method and terrestrial olivine by XPS, Mössbauer, magnetic and EPR methods

“…3a). The temperature www.crt-journal.org dependence of the EPR spectra was studied in temperature range from 300 K to 80 K. The observation the resolved EPR spectra at low temperatures and the lack of temperature dependence of linewidths mean that Mn 2+ impurity there is in our forsterite with concentration of several hundred ppm and no interaction occur between iron and manganese ions [16].…”

EPR of Gd3+-Doped La0.9Nd0.1F3Crystal: Spin-Phonon Interactions and Spin-Lattice Relaxations

“…1 F3 (the remaining neighbors are Lai+ ions), rjk' are the distances between the j and k' ions, and γjk' are the direction cosines of rjk with the magnetic field B || Z.T h e G d 3 + -N d 3 + a v e r a g e p a i r e x c h a n g e -i n t e r a c t i o n constant Jp (Hp = Jp SS') is estimated for the paramagnetic host La0.9Nd0.1F3 to be Jp = -2.7 ± 0.5 GHz [15]. The effective host g' value is determined from the Boltzmann weighting of the gi value for each of the five Kramers doublets in the 4I9/2 ground multiplet of Nd3+ ion in La0.9Nd0.1F3 as follows [39]:…”