Electron paramagnetic resonance study of Mn²⁺ in ferroelectric lithium ammonium tartarate monohydrate

Abstract

EPR studies of Mn²⁺ in ferroelectric lithium ammonium tartarate monohydrate (LAT) show that there are four Mn²⁺ complexes, which group themselves into two chemically different sets each containing two physically related sites at room temperature. It is inferred that Mn²⁺ enters into NH₄⁺ site. The hyperfine separation of the central group ( ½ →-½) is found to be constant, which is not observed usually. It is suggested that the space group of LAT below T_c is P2₁.