Highly proton-ordered water structures on oxygen precovered Ru{0001}

Avidor, N., Hedgeland, H., Held, G., Jardine, A. P., Allison, W., Ellis, J., Kravchuk, T. and Alexandrowicz, G. (2011) Highly proton-ordered water structures on oxygen precovered Ru{0001}. Journal of Physical Chemistry A, 115 (25). pp. 7205-7209. ISSN 1089-5639 doi: 10.1021/jp200221b

Abstract/Summary

We present helium scattering measurements of a water ad-layer grown on a O(2 1)/Ru(0001) surface. The adsorbed water layer results in a well ordered helium diffraction pattern with systematic extinctions of diffraction spots due to glide line symmetries. The data reflects a well-defined surface structure that maintains proton order even at surprisingly high temperatures of 140 K. The diffraction data we measure is consistent with a structure recently derived from STM measurements performed at 6 K. Comparison with recent DFT calculation is in partial agreement, suggesting that these calculations might be underestimating the contribution of relative water molecule orientations to the binding energy.