Valence fluctuation and magnetic frustration in Ga substituted YMnO3

Ga substituted YMnO3 has been studied using XPS, dc magnetization and Raman measurements. XPS measurements show mixed valency of 2+ and 4+ for manganese ions, which is consistent with magnetization measurements. XPS and magnetization measurements on Ga substituted samples provide evidence for stabilization of manganese 3+ valency as Ga concentration is increased. The magnetic frustration factor is also found to be influenced by the substitution.