The spin-phonon interaction in FeF2 and MnF2 studied by Raman spectroscopy

A temperature-dependent study of the four Raman-active phonons in MnF2 and FeF2 has shown that their Raman frequencies and intensities are affected to varying extents by the antiferromagnetic ordering. A theory for spin-dependent effects in rutile structure antiferromagnets has been developed to calculate the anomalous variation in the phonon frequency and to estimate the corresponding spin-phonon coupling coefficients.