Pairwise Interactions of Fe3+ Ions in InBO3 Crystals

Measurements of the electron paramagnetic resonance (EPR) of Fe³⁺ ion pairs in InBO₃ crystals are conducted. Some parts of the procedure of spectrum identification without measuring the temperature dependence of the resonant line intensities have been developed. Experimental curves of the second- and fourth-order axial Hamiltonian constants D _S and (a – F)_S, respectively, of the total spin number S are constructed. The single-ion second-order axial constant D _c is well described by a linear dependence on S. The constant (a – F)_S has a quadratic dependence.