Electron spin resonance and magnetization studies of Bi1−xCaxMnO3

The electron spin resonance (ESR) and magnetization measurements were carried out on Bi1−xCaxMnO3 (0.3≤x≤0.9) samples synthesized by sol-gel method. The temperature dependence of inverse of double integrated intensity (1/DI), peak to peak linewidth of the ESR signal and magnetization data are used to get information about magnetic interactions. The estimated values of charge ordering temperature (TCO) and long range antiferromagnetic (AFM) ordering i.e., Néel temperature (TN) are used to construct the magnetic phase diagram of the system. The paramagnetic (PM) to AFM transition at ~150 K co-exists with PM to canted antiferromagnetic (C-AFM) transition at ~120 K for samples with 0.5≤x≤0.8. Whereas only PM to C-AFM transition is observed for samples with x=0.85 and 0.90.