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Adsorbate-induced Surface Stiffening: Surface Lattice Dynamics of Ru(001)-(1x1)-O

T. Moritz·W. Widdra·D. Menzel·K. -P. Bohnen·R. Heid
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Abstract

The dynamical properties of the high-density Ru(001)-(1$\times$1)-O phase has been investigated by a combined high-resolution electron energy loss spectroscopy and density functional theory study. Due to a strong static outward relaxation of the first Ru layer a soft Rayleigh phonon mode is expected. However, a Rayleigh mode stiffening together with a new high energy in-plane phonon mode above the bulk bands is found which is related to a strong adsorbate-induced intralayer force constant stiffening which counteracts an interlayer softening. This structurally rather simple system with one surface atom per (1$\times$1) unit cell demonstrates the limited applicability of previously adopted models.

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T. Moritz, W. Widdra, D. Menzel, K. -P. Bohnen, R. Heid. 2002-11-29. Adsorbate-induced Surface Stiffening: Surface Lattice Dynamics of Ru(001)-(1x1)-O. https://arxiv.org/abs/cond-mat/0211704

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