First-Principles Calculations of Glycine Formation on Cu(110) Surface

The geometrical structures of singlet or triplet NCH3 molecules adsorbing on Cu(110) surface with presence of Cu adatoms have been determined by first-principle calculation method. The two distinguishable structures match the patterns of experimental scanning tunneling microscopy (STM) image, so-called zigzag and rectangle structures. The singlet NCH3 molecules arrange as zigzag, when the triplet NCH3 molecules array as rectangle. Since NCH3 can be found in interstellar environment and its radicals are chemically active, we arise a question whether this system can be utilized to study surface chemical reaction of interstellar medium (ISM). Therefore, the potential surface of NCH3 isomerization to HNCH2 subsequently binding with CO on Cu(110) surface has been calculated using density functional theory (DFT). The calculation results that HNCH2-CO can be produced on triplet state. However, the reaction is endothermic which is assumed to be occurred at warmer regions of solar systems or in specific planets having terrestrial heat (like Earth).