Physical properties and magnetic structures of the metallic antiferromagnet <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>CeMn</mml:mi> <mml:mrow> <mml:mn>0.84</mml:mn> </mml:mrow> </mml:msub> <mml:msub> <mml

We report the magnetic and transport properties of ${\mathrm{CeMn}}_{0.84}{\mathrm{Sb}}_{2}$ measured on single-crystal samples as well as the magnetic structures determined by neutron diffraction using a powder sample. The results of magnetic and transport measurements below room temperature show that ${\mathrm{CeMn}}_{0.84}{\mathrm{Sb}}_{2}$ exhibits metallic conduction and undergoes three magnetic transitions at ${T}_{1},{T}_{2}$, and ${T}_{3}$, where ${T}_{1}&gt;{T}_{2}&gt;{T}_{3}$, indicating the existence of three distinct magnetic phases (I, II, and III). The magnetization and the magnetoresistance effect exhibit characteristic behaviors that can be ascribed to field-induced magnetic transitions. The results of powder neutron diffraction indicate the formation of antiferromagnetic orders with a propagation vector of (0, 0, 1/2) below ${T}_{1}$. Rietveld refinements reveal that the Mn moments align along the $c$ axis at 160 K (phase I) and cant toward the $ab$ plane at lower temperatures (phase II). With a further decrease in the temperature, both Mn and Ce moments order in phase III.