Mg-Containing Zn3O3 Structures for Detection of CO2: A DFT Study on CHEM Effects of SERS and Electronic Properties

This computational study asks whether small Zn3O3 clusters, with and without magnesium, could sense CO2 through the chemical enhancement side of SERS (surface-enhanced Raman spectroscopy). In density functional theory calculations at the B3LYP level, the magnesium site came out as the preferred spot for CO2 adsorption, and Raman activity for the symmetric CO2 stretch rose most on Zn3O3Mg, the structure holding magnesium in an interstitial position. Excited-state and charge-transfer calculations indicated this structure would suit CO2 sensing at visible wavelengths by the resonance Raman effect, pointing to which compositions are worth making.