First principles calculations of methylamine and methanol adsorption on hydroxylated quartz (0Â 0Â 0Â 1)

Density functional theory calculations have been used to study the adsorption of methylamine and methanol on the hydroxylated (0 0 0 1) surface of α-quartz. The surface structure for these calculations was based on the structure reported recently by Goumans et al. [T.P.M. Goumans, A. Wander, W.A. Brown, C.R.A. Catlow, Phys. Chem. Chem. Phys. 9 (2007) 2146]. Adsorption of methylamine or methanol in their most energetically preferred sites occurs by breaking one of the hydrogen bonds that exists on the bare surface and creating two hydrogen bonds between the surface and the adsorbed molecule. We report the adsorption energy and the vibrational frequencies associated with adsorption of these two species. Understanding the adsorption of these species on α-quartz (0 0 0 1) will be useful in future consideration of the adsorption of chiral molecules such as amino acids on this surface, which is intrinsically chiral.