Trigonal ${\mathrm{Cr}}_{1+\delta }{\mathrm{Te}}_2$ is a well-known ferromagnetic material that has recently drawn much attention due to the discovery of a zero-field skyrmion state, an unusual anomalous Hall effect, a topological Hall effect, and a topological Nernst effect. This quasi-van der Waals layered material with intercalated Cr atoms possesses many peculiar features that depend on the amount of Cr intercalation, although the microscopic magnetic ground state is still elusive. We reveal the structural and magnetic properties of trigonal ${\mathrm{Cr}}_{1.22}{\mathrm{Te}}_2$ by low-temperature x-ray diffraction, magnetization, temperature-dependent Raman spectroscopy, and single-crystal neutron-diffraction studies. Magnetization measurements under small applied magnetic field indicate two successive magnetic transitions, one from a ferromagnetic (FM) state to an antiferromagnetic (AFM) state ($T_{\mathrm{C}}=197\mathrm{K}$) and second from an AFM state to a paramagnetic state ($T_{\mathrm{N}}=211\mathrm{K}$). The FM transition is sharp with a strong presence of magnetoelastic coupling, but is not accompanied by any structural phase transition. The magnetic structure obtained from zero-field single-crystal neutron diffraction reveals that the Cr1 and Cr2 moments are ferromagnetically aligned along the $c$ axis, while the Cr3 and intercalated Cr4 atoms induce an AFM component in the $ab$ plane leading to an umbrellalike spin structure which possesses a finite spin chirality. The presence of a finite spin chirality is responsible for the observation of the topological Hall effect.

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• Magnetic order
• Magnetic phase transitions
• Magnetic texture
• Magnetism
• Chiral magnets
• van der Waals systems
• Neutron diffraction
• Raman spectroscopy
• X-ray powder diffraction