  Theoretical DFT calculations using GGA+U and HSE06 frameworks enabled
vibrational mode assignment and partial (atomic) phonon DOS determination in
KAgF3 perovskite, a low-dimensional magnetic fluoroargentate(II). Twelve bands
in the spectra of KAgF3 were assigned to either IR active or Raman active
modes, reaching very good correlation with experimental values (R2>0.997).
Low-temperature Raman measurements indicate that the intriguing
spin-Peierls-like phase transition at 230 K is an order-disorder transition and
it does not strongly impact the vibrational structure of the material.
