Spinel Co_1−xSr_xFe₂O₄ nanoferrites were synthesized by co-precipitation method.

Obtained parameters showed dependence on the Sr²⁺ ion content x.

IR bands; ν₁ and ν₂ were affected by M_s, whereas M_s proved dependence on R.

Elastic moduli and Debye temperature pointed to increase in the sample rigidity.

High concentration of Sr²⁺ ions causes their deposition on the grain boundaries.