On the temperature induced transformation between the two Al(111)-(√3 × √3)R30°-Rb structures

• The dynamics of the temperature induced transformation between low and high temperature adsorption phases of Rb on Al(111) has been followed by high resolution core level spectroscopy. Particular emphasis has been paid to the order-preserving transformation between the low and high temperature Al(111)-Rb-(√3 × √3)R30° structures in which Rb atoms occupy on-top and substitutional sites, respectively. For a Rb coverage of 0.33 monolayer the rate of conversion from on-top ti substitutional sites is found to increase strongly at 250 K. For Rb coverages below 0.33 but above approximately 0.14 monolayers the conversion occurs at lower temperatures. Increasing the coverage above 0.33 monolayers increases the conversion temperature. The possibility to detect the Al atoms which are expelled from the first Al layer during the conversion is demonstrated.

Keyword

Alkali metals

Aluminum

Photoelectron emission

Single crystal surfaces

Soft X-ray photoelectron spectroscopy

Surface relaxation and reconstruction

Surface thermodynamics

Publication and Content Type

art (subject category)

ref (subject category)