  We have investigated magnetic, dielectric and magnetodielectric properties of
La2CoMnO6 nanoparticles prepared by sol-gel method. Magnetization measurements
revealed two distinct ferromagnetic transitions at 218 K and 135 K that can be
assigned to ordered and disordered magnetic phases of the La2CoMnO6
nanoparticles. Two dielectric relaxations culminating around the magnetic
transitions were observed with a maximum magnetodielectric response reaching
10% and 8% at the respective relaxation peaks measured at 100 kHz under 5T
magnetic field. The dc electrical resistivity followed an insulating behavior
and showed a negative magnetoresistance; there was no noticeable anomaly in
resistivity or magnetoresistance near the magnetic ordering temperatures.
Complex impedance analysis revealed a clear intrinsic contribution to the
magnetodielectric response; however, extrinsic contribution due to
Maxwell-Wagner effect combined with magnetoresistance property dominated the
magnetodielectric effect at high temperatures.
