Investigating Water Sensing Capabilities of Ca‐ and Sr‐Containing (BaTiO3)3 Clusters: A Computational Study of Electronic Properties and Chemical Effects in Surface‐Enhanced Raman Spectroscopy

This computational study tests whether small barium titanate clusters doped with calcium or strontium could serve as substrates for detecting water by surface-enhanced Raman scattering (SERS), which amplifies the weak Raman signal of adsorbed molecules. Cluster geometries were optimised with density functional theory (M06/6-31G(d,p)), and the results indicated that Ca or Sr at interstitial sites raised binding energy per atom, while adsorbed water shifted electronic polarizability and increased Raman activity for water’s vibrational modes. Water-detecting nanomaterials have industrial and environmental uses, and the authors put the doped clusters forward as promising SERS substrates.