Exploring the uncharacterized magnetic phases of Co2+ chain compounds is critical for finding new low-dimensional magnets hosting quantized excitations. We map the unexplored magnetic phases of the Co2+ chain compound Li2CoCl4. Magnetometry reveals magnetic ordering below 7 K with a metamagnetic transition near 16.5 kOe and a gradual transition to a field-aligned paramagnetic state above 31 kOe. Curie-Weiss fits to the high-temperature susceptibility reveal a high-spin (spin-32) state for cobalt. Heat capacity data, though, give a magnetic entropy change of 5.46 J/mol, consistent with cobalt effective spin-12 systems. To characterize the zero-field antiferromagnetic ordering, we separately calculated the energy of proposed magnetic structures with density functional theory and collected 3.5 K neutron diffraction data, finding that Li2CoCl4 has ferromagnetic chains with antiferromagnetic interactions between them. Increasing field rotates these spin chains, producing the antiferromagnetic to intermediate to paramagnetic transition sequence.
ASJC Scopus subject areas
- Materials Science(all)
- Physics and Astronomy (miscellaneous)