Exchange interactions in the Cr$^{3+}$–Cr$^{3+}$ ion pair in the ABO$_{3}$ ($A$ = Ga, In, Sc) diamagnetic matrix

The exchange interactions in the Cr$^{3+}$–Cr$^{3+}$ ion pairs in the isostructural ABO$_{3}$ ($A$ = Ga, In, Sc) diamagnetic compounds have been examined using the magnetic resonance technique. The values of bilinear and biquadratic exchange interactions have been determined. It is shown that the biquadratic exchange in the Cr$^{3+}$–Cr$^{3+}$ pair in these compounds is caused by the exchange striction.