  New phenomenon is experimentally identified: ferroelectrical spin wave
resonance (FE SWR), which consist in characteristic splitting of vibration
(electronic-vibration) levels in optical spectra of interacting localized
centers. Spectral positions of ESWR lines are determined in linear approach by
quadratic dispersion law. It has been found that the values of resonance mode
amplitudes are inversely proportional to mode numbers (by low excitation
level). The prediction that Raman-ESWR and IR-ESWR are characterized by
splitting constants with different values has been confirmed. Their ratio is
approximately equal two (by the frequencies of zero modes reduced to the same
value). It is independent argument for FE SWR identification.
