Assessment of heterochiral and homochiral glycine adlayers on Cu(1 1 0) using density functional theory

We have used plane wave density functional theory (DFT) to determine the structure and relative energy of two possible (3 × 2) glycine adlayers on Cu(1 1 0), namely, heterochiral and homochiral adlayers. Our calculated heterochiral structure is in quantitative agreement with previous X-ray photoelectron diffraction experiments, but our calculated homochiral structure is inconsistent with this experimental data. Our calculations also indicate that the heterochiral (3 × 2) adlayer is significantly more energetically stable than the homochiral (3 × 2) adlayer. Our results indicate that large regions of the homochiral (3 × 2) glycine adlayer are unlikely to exist on Cu(1 1 0).