The local structural response to magnetic ordering in polycrystalline ${\mathrm{Cr}}_{0.3}{\mathrm{Fe}}_{0.7}{\mathrm{VO}}_4$ has been examined using synchrotron x-ray diffraction, x-ray absorption fine structure, and Raman spectroscopy. The combined structural analyses indicate that the average M-O (M = Cr/Fe) and V-O coordination environments remain essentially unchanged across the magnetic transition $T_N\simeq 21\mathrm{K}$, implying that nearest-neighbor bond distortions do not play a role in driving the magnetic ordering. Instead, subtle modifications occur at $T_N$ in the intercluster M-O-V linkages, consistent with tilting and/or rotation of ${\mathrm{MO}}_6$ octahedra and ${\mathrm{VO}}_4$ tetrahedra. EXAFS analysis further identifies a tendency toward preferential occupation of the more distorted ${\mathrm{M}}_1$ sites by ${\mathrm{Cr}}^{3+}$ and the more regular ${\mathrm{M}}_2$ sites by ${\mathrm{Fe}}^{3+}$, which shapes the mixed ${\mathrm{d}}^3$–${\mathrm{d}}^3, {\mathrm{d}}^3$–${\mathrm{d}}^5$, and ${\mathrm{d}}^5$–${\mathrm{d}}^5$ exchange interactions in the ${\mathrm{M}}_4{\mathrm{O}}_{16}$ clusters. We propose that five competing superexchange pathways within each cluster give rise to intrinsic intracluster frustration and short-range ordering, which propagates through M-O-V-O-M linkages to modulate geometric frustration at larger length scales. Raman measurements reveal only weak spin-phonon coupling confined to a narrow temperature region of 15–25 K, tentatively attributed to this frustration. These results suggest a hierarchical frustration scenario in which the local cation distribution shapes the exchange network, whereas the subtle interpolyhedral distortions represent a structural response coupled to the evolving magnetic correlations. These interpretations are inferred from structural and macroscopic magnetic data, and direct validation by neutron diffraction, $\mu \mathrm{SR}$, or density functional theory (DFT) calculations is needed.

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• Lattice dynamics
• Magnetic interactions
• Microstructure
• Spin-phonon coupling
• Antiferromagnets
• Polycrystalline materials
• Magnetization measurements
• Raman spectroscopy
• X-ray absorption spectroscopy
• X-ray diffraction