Structural characterization and magnetic properties of iron-phosphate glass prepared by sol-gel method

•Sol-gel synthesized and heated xFeP samples with ‘x’ of 40, 50, 60, 70 and 80 resulted in the formation of FeIII(distorted octahedral) and FeII(octahedral) coordination.•Magnetic susceptibility results indicate that only 50FeP glass heat-treated at 200°C shows spin glass behavior and all other glasses are superparamagnetic at low temperatures.•The Weiss temperatures (θw) obtained for all the glasses were negative, suggesting that the interaction between the magnetic moments is antiferromagnetic.