The family of topological semimetals $Ln{\mathrm{Sb}}_x{\mathrm{Te}}_{2-x-\delta }$ allows for the study of the interplay between electronic, magnetic, and structural properties by adjusting chemical pressure through the choice of lanthanide $\left(Ln\right)$ and band filling through Te doping. Previous reports indicated that the choice of $Ln$ may affect the magnetic ordering of spins and that the Sb/Te composition may affect the structural order in the square net. Here, we focus on the structural evolution of ${\mathrm{PrSb}}_x{\mathrm{Te}}_{2-x-\delta }$, with emphasis on the evolving structural modulation. Single-crystal diffraction reveals charge density wave (CDW) modulations that evolve with band filling. In an intermediate band-filling regime, selected-area electron diffraction shows that the magnitude of the single CDW wave vector varies approximately linearly with band filling. By contrast, at high band filling the system stabilizes three fixed, commensurate CDW wave vectors. We report two new modulated structure solutions of the family and compare the structural range of Pr against other $Ln$ in $Ln{\mathrm{Sb}}_x{\mathrm{Te}}_{2-x-\delta }$. Lastly, we find that in the single-q CDW regime, compounds with larger lanthanide ionic radii tend to reach shorter-period commensurate supercells, whereas smaller-$Ln$ members stabilize longer-period commensurate structures.

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• Charge density waves
• Doping effects
• Magnetic order