Phonon fingerprints of CsPb<sub>2</sub>Br<sub>5</sub>
Phonon fingerprints of CsPb<sub>2</sub>Br<sub>5</sub>
CsPb2Br5 is a stable, water-resistant, material derived from CsPbBr3 perovskite and featuring two-dimensional Pb-Br framework separated by Cs layers. Both compounds can coexist at nano- length scale, which often produces conflicting optical spectroscopy results. We present a complete set of polarized Raman spectra of nonluminescent CsPb2Br5 single crystals that reveals …