Magnetic phase transitions in the Gd1 − xTmxMn6Sn6 compounds

The magnetic properties of the HfFe6Ge6-type Gd1 − xTmxMn6Sn6 (0 ≤ x ≤ 0.9) compounds have been investigated in the temperature range of 5-600 K. The compounds with x ≤ 0.8 are ferrimagnetic in the whole temperature range. The ferrimagnetic Curie temperatures decrease with increasing Tm content from 435 K (x = 0) to 344 K (x = 0.9). The samples with x = 0.85 and 0.9 show paramagnetic-ferrimagnetic-antiferromagnetic-ferrimagnetic phase transitions with decreasing temperature. For the x = 0.85 compound, the metamagnetic phase transition from antiferromagnetism to ferrimagnetism is induced by an applied field 20 kOe.