Inadequate unit selection for diffuse reflectance FT-IR spectra conceals low intensity bands of adsorbates

Key Points

• To evaluate how inadequate unit selection affects the interpretation of low intensity bands in diffuse reflectance FT-IR spectra.
• Analyzed diffuse reflectance FT-IR spectra using the Kubelka–Munk transformation.
• Compared perceived site speciation before and after applying the transformation.
• Investigated effects of unit selection on band intensities.
• Low intensity bands of adsorbates were significantly squashed by the Kubelka–Munk transformation.
• Misrepresentation of site speciation was observed when inadequate units were used.
• Study emphasizes the need for proper unit selection for accurate spectral analysis.