We present a facile method for the determination of the electromagnetic field enhancement of nanostructured TiN electrodes using surface-enhanced Raman spectroscopy. As a model system, TiN with partially collapsed nanotube structure obtained from the nitridation of TiO2 nanotube arrays was used. Using surface-enhanced Raman scattering (SERS) spectroscopy, the electro-magnetic field enhancement factors (EFs) of the substrate across the optical region were deter-mined. The non-surface binding SERS reporter group azidobenzol was chosen, for which con-tributions from the chemical enhancement effect can be minimized. Derived EFs correlated with the electronic absorption profile and reached 3.9 at 786 nm excitation. Near-field enhancement and far-field absorption simulated with rigorous coupled wave analysis showed good agreement with the experimental observations. From the calculations, the major optical activity of TiN was con-cluded to originate from collective localized plasmonic modes at ca. 700 nm arising from the specific nanostructure.

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