Infrared absorption spectra of a Nd$_{0.5}$Ho$_{0.5}$Fe$_{3}$(BO$_{3}$)$_{4}$

Infrared absorption spectra of a Nd$_{0.5}$Ho$_{0.5}$Fe$_{3}$(BO$_{3}$)$_{4}$ crystal in the spectral range of 30–1700 cm$^{-1}$ have been measured at temperatures from 6 to 300 K. The experimental spectra have been analyzed based on the semiempirical calculation of the lattice dynamics and the analysis of correlation diagrams of borate complexes. No changes associated with structural phase transitions have been detected in the temperature range of measurements; the effect of magnetic ordering on the infrared absorption spectra has not been observed.