TY - JOUR

T1 - Two-stage ordering processes under annealing of Sr submonolayers on Mo(1 1 2)

AU - Fedorus, A.

AU - Godzik, G.

AU - Naumovets, A.

AU - Pfnür, Herbert

N1 - Funding information: This work was supported by the National Academy of Sciences of Ukraine (project VTs-92) and by the Basic Research Foundation of the Ministry of Ukraine for Education and Science (project 02.07/00047). Support by the Deutsche Forschungsgemeinschaft is also gratefully acknowledged.

PY - 2004/7/23

Y1 - 2004/7/23

N2 - Using LEED as technique of investigation, the evolution of geometrical order in the system Sr/Mo(1 1 2) was studied after annealing at temperatures between 100 and 900 K. Two stages of ordering were found for the chain-like structures p(8 × 1) and p(5 × 1). Partial ordering occurred already at the base adsorption temperature (90 K) with slight improvement after annealing to temperatures around 200 K. The full equilibration of the layers, however, was found to happen only at high annealing temperatures (ranging between 500 and 600 K, depending on coverage). Correlating these data with the highly anisotropic diffusivity known for Sr overlayers on Mo(1 1 2), we assume that the low-temperature ordering sets in via a kink-like diffusion of adsorbate chains essentially along the substrate troughs, whereas in the high-temperature step, diffusion across the troughs is most important.

AB - Using LEED as technique of investigation, the evolution of geometrical order in the system Sr/Mo(1 1 2) was studied after annealing at temperatures between 100 and 900 K. Two stages of ordering were found for the chain-like structures p(8 × 1) and p(5 × 1). Partial ordering occurred already at the base adsorption temperature (90 K) with slight improvement after annealing to temperatures around 200 K. The full equilibration of the layers, however, was found to happen only at high annealing temperatures (ranging between 500 and 600 K, depending on coverage). Correlating these data with the highly anisotropic diffusivity known for Sr overlayers on Mo(1 1 2), we assume that the low-temperature ordering sets in via a kink-like diffusion of adsorbate chains essentially along the substrate troughs, whereas in the high-temperature step, diffusion across the troughs is most important.

KW - Low energy electron diffraction (LEED): Alkaline earth metals

KW - Molybdenum

KW - Surface diffusion

KW - Surface thermodynamics (including phase transitions)

UR - http://www.scopus.com/inward/record.url?scp=4344718901&partnerID=8YFLogxK

U2 - 10.1016/j.susc.2004.07.008

DO - 10.1016/j.susc.2004.07.008

M3 - Article

AN - SCOPUS:4344718901

VL - 565

SP - 180

EP - 190

JO - Surface Science

JF - Surface Science

SN - 0039-6028

IS - 2-3

ER -