A first-principles study of methyl lactate adsorption on the chiral Cu (643) surface

- Dispersion accounts for 60-80% of Eads for methyl lactate on the Cu surface.
- S-methyl lactate binds more strongly than R-methyl lactate on Cu (643)R.
- DFT with dispersion matches experimental enantiospecific peak temperatures.

We used dispersion-corrected density function theory (DFT) to investigate the enantiospecific adsorption of R- and S-methyl lactate on the chiral Cu (643)R surface. Initial study of methyl lactate adsorbed on the Cu (111) surface revealed that the most strongly bound states are associated with interaction of the hydroxyl and alkoxide group with the surface. Using dispersion-corrected DFT-derived pre-factors and desorption energies within the Redhead analysis predicts peak temperatures that are in relatively good agreement with experimental values for molecular methyl lactate desorption from both the Cu (111) and Cu (643)R surface. The global minimum of S-methyl lactate is more firmly bound by 9.5 kJ/mol over its enantiomer on the Cu (643)R surface, with a peak temperature difference of 25 K versus an experimental value of 12 K.