Incommensurate–commensurate magnetic phase transition in double tungstate Li₂Co(WO₄)₂

Abstract

Magnetic susceptibility, specific heat, and neutron powder diffraction measurements have been performed on polycrystalline Li2Co(WO4)2 samples. Under zero magnetic field, two successive magnetic transitions at T N1 ∼ 9.4 K and T N2 ∼ 7.4 K are observed. The magnetic ordering temperatures gradually decrease as the magnetic field increases. Neutron diffraction reveals that Li2Co(WO4)2 enters an incommensurate magnetic state with a temperature dependent k between T N1 and T N2. The magnetic propagation vector locks-in to a commensurate value k = (1/2, 1/4, 1/4) below T N2. The antiferromagnetic structure is refined at 1.7 K with Co2+ magnetic moment 2.8(1) μ B, consistent with our first-principles calculations.

Evolution of Magnetism Induced by K+/La3+ Implantations in Double Perovskite Ba2MnTeO6

“…Polycrystalline BMTO, BKMTO, and BLMTO have been synthesized by the solid-state reaction method. − Selected raw materials including barium carbonate (BaCO 3 , 99.99%), manganese dioxide (MnO 2 , 99.99%), tellurium dioxide (TeO 2 , 99.99%), potassium carbonate (K 2 CO 3 , 99.99%), and lanthanum trioxide (La 2 O 3 , 99.99%) were weighed according to the molar ratio and fully ground with acetone. It is worth noting that a 20% excess of the alkali carbonate is necessary to compensate for the loss due to volatilization.…”