Zone center phonons of the orthorhombic RMnO3 (R = Pr, Eu, Tb, Dy, Ho) perovskites

TL;DR

This study applies a short range force constant model to analyze phonons in orthorhombic RMnO3 perovskites, successfully predicting Raman and infrared frequencies and providing new assignments for the latter.

Contribution

First application of SRFCM to RMnO3 perovskites, accurately predicting phonon frequencies and assigning infrared modes for the orthorhombic phase.

Findings

Good agreement with observed Raman frequencies

Infrared frequencies assigned for the first time

Model uses 17 force constants

Abstract

A short range force constant model (SRFCM) has been applied for the first time to investigate the phonons in RMnO3 (R = Pr, Eu, Tb, Dy, Ho) perovskites in their orthorhombic phase. The calculations with 17 stretching and bending force constants provide good agreement for the observed Raman frequencies. The infrared frequencies have been assigned for the first time. PACS Codes: 36.20.Ng, 33.20.Fb, 34.20.Cf