A new ternary carbide Dy2Mn2-xC5 (x=0.6): Preparation, crystal structure, and physical properties

作者：Levytskyy V; Babizhetskyy V^*; Magun A; Heinrich P; Salamakha L; Bauer E; Michor H; Kotur B

来源：Journal of Physics and Chemistry of Solids, 2015, 79: 72-77.

DOI：10.1016/j.jpcs.2014.12.002

• Inorganic compounds
• Crystal structure
• Magnetic properties
• Electrical properties

The crystal structure, magnetic and electrical transport properties of the new ternary compound Dy2Mn2-xC5 (x=0.6) have been investigated. According to X-ray powder diffraction the carbide crystallizes in its own structure type, space group I4/mmm, a=3.6421(2), c=15.7713(9) angstrom, R-B=0.062, R-p=0.134. The crystal structure contains isolated carbon atoms and C-2 dimers in square-bipyramidal holes and distorted bicapped square anti-prisms, respectively. Manganese atomic positions in the structure were found to be not fully occupied. Physical properties were studied in the temperature range down to 0.4 K. The electrical resistivity of Dy2Mn2-xC5 (x=0.6) reveals its basically metallic nature with a positive temperature coefficient above about 30 K. A resistive anomaly at around 20 K indicates the appearance of an antiferromagnetic superzone boundary gap at low temperatures. A phase transition towards long range antiferromagnetic magnetic ordering below 19 K is further revealed by heat capacity and ac susceptibility data. Magnetization data refer to a non-trivial nature of the magnetic ground state which may be caused by the intrinsic structural disorder associated with random vacancies at the Mn site.

• 出版日期2015-4