= Solution
An N-bound <thiocyanate> need not make an exactly linear Eu–N–C linkage. Eu(III) bonding is predominantly electrostatic, with weak directional covalent contributions from the shielded $4f$ orbitals. There is consequently less energetic reward for enforcing a precisely collinear metal–donor arrangement than in a strongly directional transition-metal <pi bond>. In the crowded eight-coordinate sphere, bending the external NCS groups can reduce ligand–ligand repulsion while retaining favourable Eu–N distances. \b[Angles of $150^\circ$–$160^\circ$ are compatible with bent N coordination]; they do not require changing the linkage to sulfur. This concerns the Eu–N–C angle, not bending the internal N–C–S skeleton.
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