The magnetic properties of transparent pink Na2Mn3Cl8 and NaMnCl3 are presented. For both phases, the effective magnetic moments are large, while the Curie-Weiss thetas are below 10 K. The compounds crystallize in the trigonal R-3m and R-3 space groups, respectively. A Kagome plane of Mn2+ octahedrally coordinated to Cl− is found in Na2Mn3Cl8 and the material has no apparent magnetic ordering above 1.8 K, while the octahedrally coordinated, honeycomb network of Mn2+ in NaMnCl3 orders antiferromagnetically at 6.3 ± 0.2 K. The heat capacity of NaMnCl3 has one transition, consistent with the susceptibility, while Na2Mn3Cl8 exhibits a more complex heat capacity with two peaks, at 0.6 K and 1.4 K. A third, broad peak near 6.2 K in the heat capacity of Na2Mn3Cl8 is problematic but may be due to the intergrowth of NaMnCl3 domains.
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Materials Chemistry
- Heat capacity
- Magnetic frustration