Coverage-dependent frequency for Li-atom vibrations on Cu(111).

نویسندگان

  • Lindgren
  • Svensson
  • Walldén
  • Carlsson
  • Wahlström
چکیده

Electron-energy-loss spectra recorded for monolayer amounts of Li adsorbed on Cu~111! show a loss peak associated with Li vibrations perpendicular to the substrate. The loss energy shifts from 38 meV at low coverage to 43 meV at 0.3 ML and remains constant for coverages between 0.3 and 0.5 ML. The loss intensity passes a maximum at a Li coverage of 0.15 ML and gradually decreases such that it is difficult to resolve a loss peak at coverages above 0.5 ML. The high loss energy indicates that the adatom resides on the surfaces rather than in substitutional sites. The frequency shift is much too large to be explained by dipole-dipole interactions. The above results are obtained with the evaporation source loaded with the natural Li isotope mixture ~92.6% Li, 7.4% Li!. Measurements with Li show that the increase of the vibration frequency with increasing coverage is not an isotope effect. @S0163-1829~96!09439-8#

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A combined He - atom scattering and theoretical study of the low energy vibrations of physisorbed monolayers of Xe on Cu ( 111 ) and Cu ( 001 )

A combined He-atom scattering and theoretical study of the low energy vibrations of physisorbed monolayers of Xe on Cu(111) and Cu(001) Abstract The surface phonon dispersion curves of commensurate Xe monolayers on Cu(111) and incommensurate Xe monolayers on Cu(001) surfaces have been measured using He atom scattering (HAS) time of flight (TOF) spectroscopy. The TOF spectra are interpreted by c...

متن کامل

Collisional line shapes for low frequency vibrations of adsorbates on a metal surface.

The dynamics of atoms or molecules adsorbed on a metal surface, and excited by collisions with an atomic beam, are treated within a theory that includes energy dissipation into lattice vibrations by means of a frequency and temperature dependent friction function. The theory provides dynamic structure factors for energy transfer derived from collisional time correlation functions. It describes ...

متن کامل

Bromine atom diffusion on stepped and kinked copper surfaces

The rates of Br atom diffusion on several single crystalline Cu surfaces have been studied because of the potential impact of Br diffusion on the selectivity of alkyl bromide surface chemistry on Cu. Density functional theory (DFT) has been used to study the diffusion of isolated bromine atoms on a flat Cu surface, Cu(111), two Cu surfaces with straight steps, Cu(221) and Cu(533), and two kinke...

متن کامل

Hydrogen-bonded assembly of methanol on Cu(111).

Investigation of methanol's surface chemistry on metals is a crucial step towards understanding the reactivity of this important chemical feedstock. Cu is a relevant metal for methanol synthesis and reforming, but due to the weak interaction of methanol with Cu, an atomic scale view of methanol's coverage-dependent ordering and self-assembly on Cu(111), the most abundant facet of most nanoparti...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:
  • Physical review. B, Condensed matter

دوره 54 15  شماره 

صفحات  -

تاریخ انتشار 1996