Evidence is presented to show that the two-dimensional effective interaction between He atoms on graphite is less attractive than the free-space interaction Vo. The principal origin of the effect is substrate screening of the attraction. A small shift arises also from averaging the adatom motion perpendicular to the surface. The revised potential Veff is shown to yield improved agreement for the specific heat in the low-coverage region where a quantum virial expansion applies.
|Original language||English (US)|
|Number of pages||5|
|Journal||Physical Review B|
|State||Published - Jan 1 1980|
ASJC Scopus subject areas
- Condensed Matter Physics