We show that vibrational spectra of molecules chemisorbed on metal surfaces can be affected by anharmonicity much more than usually estimated if various vibrational coordinates are coupled by non-diagonal terms. The strong coverage dependence of the linewidth of the adsorbate-metal vibrations of CO adsorbed on Pt(111) can be attributed to the multiphonon decay, enhanced by a strong coupling of the adsorbate motion to the in-plane displacement of the surrounding surface atoms. © 1995.
Brako, R., & Brenig, W. (1995). Vibrational linewidth of CO adsorbed on Pt(111). Surface Science, 336(1–2), 27–36. https://doi.org/10.1016/0039-6028(95)00515-3