Magnetic behavior of Ba3Cu3Sc4O12

The chain-like system Ba3Cu3Sc4O12 has potentially interesting magnetic properties due to the presence of Cu2+ and a structure-suggested low dimensionality.?We present magnetization M versus magnetic field H and temperature T, T-?and H-dependent heat-capacity Cp, 45Sc nuclear magnetic resonance (NMR), muon spin rotation (?SR), neutron diffraction measurements and electronic structure calculations for Ba3Cu3Sc4O12. The onset of magnetic long-range antiferromagnetic (AF) order at TN ???16?K is consistently evidenced from the whole gamut of our data.?A significant sensitivity of TN to the applied magnetic field H (TN???0?K for H?=?70?kOe) is also reported. Coupled with a ferromagnetic Curie?Weiss temperature (?CW???65?K) in the susceptibility (from a 100 to 300?K fit), it is indicative of competing ferromagnetic and antiferromagnetic interactions. These indications are corroborated by our density functional theory based electronic structure calculations, where we find the presence of significant ferromagnetic couplings between some copper ions whereas AF couplings were present between some others. Our experimental data, backed by our theoretical calculations, rule out the one-dimensional magnetic behavior suggested by the structure and the observed long-range order is due to the presence of non-negligible magnetic interactions between adjacent as well as next-nearest chains.