Details
| Original language | English |
|---|---|
| Pages (from-to) | 1566-1573 |
| Number of pages | 8 |
| Journal | Surface Science |
| Volume | 600 |
| Issue number | 8 |
| Publication status | Published - 3 Feb 2006 |
Abstract
Using the experimental results obtained for the Dy-Mo(1 1 2) system, we discuss the possibilities and mechanisms of formation of two-dimensional (2D) glasses on metal surfaces. It has been found that in the coverage range 0.07 < θ < 0.58, ordered Dy superstructures formed and observed at T < 400 K are irreversibly destroyed by annealing to higher temperatures and turn into an amorphous (glass) structure on cooling. It is supposed that this conversion is caused by the formation, at T > 400 K, of a Dy-Mo surface alloy in which the rate of Dy surface diffusion is strongly reduced in comparison with its value in the absence of alloying. As a result, the mobility of Dy adatoms becomes too low at the temperatures corresponding to the ordered equilibrium state of the surface, and this state cannot be achieved in reasonable relaxation time. This interpretation is corroborated by the experimental data on substantial suppression of surface diffusion in some coadsorbed layers. Since surface glasses contact with ordered (crystalline) substrates, their structure may have a peculiar character different from that of "conventional" metal glasses. Surface glasses can find a number of applications as rather stable systems that combine low dimensionality, specific electronic structure of their constituents and extremely high density of defects.
Keywords
- Adsorbate structure, Glass surfaces, Glass transitions, Kinetics of annealing, LEED, Surface diffusion, Surface phase transitions, Surface structure, Work function measurements
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Materials Science(all)
- Surfaces, Coatings and Films
- Materials Science(all)
- Materials Chemistry
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In: Surface Science, Vol. 600, No. 8, 03.02.2006, p. 1566-1573.
Research output: Contribution to journal › Article › Research › peer review
}
TY - JOUR
T1 - The processes of ordering and formation of two-dimensional glasses at metal surfaces
AU - Fedorus, A. G.
AU - Mitryaev, A. A.
AU - Mukhtarov, M. A.
AU - Pfnür, Herbert
AU - Vedula, Yu S.
AU - Naumovets, A. G.
N1 - Funding information: We thank V.V. Maslov for helpful discussion. This work was supported by 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 - 2006/2/3
Y1 - 2006/2/3
N2 - Using the experimental results obtained for the Dy-Mo(1 1 2) system, we discuss the possibilities and mechanisms of formation of two-dimensional (2D) glasses on metal surfaces. It has been found that in the coverage range 0.07 < θ < 0.58, ordered Dy superstructures formed and observed at T < 400 K are irreversibly destroyed by annealing to higher temperatures and turn into an amorphous (glass) structure on cooling. It is supposed that this conversion is caused by the formation, at T > 400 K, of a Dy-Mo surface alloy in which the rate of Dy surface diffusion is strongly reduced in comparison with its value in the absence of alloying. As a result, the mobility of Dy adatoms becomes too low at the temperatures corresponding to the ordered equilibrium state of the surface, and this state cannot be achieved in reasonable relaxation time. This interpretation is corroborated by the experimental data on substantial suppression of surface diffusion in some coadsorbed layers. Since surface glasses contact with ordered (crystalline) substrates, their structure may have a peculiar character different from that of "conventional" metal glasses. Surface glasses can find a number of applications as rather stable systems that combine low dimensionality, specific electronic structure of their constituents and extremely high density of defects.
AB - Using the experimental results obtained for the Dy-Mo(1 1 2) system, we discuss the possibilities and mechanisms of formation of two-dimensional (2D) glasses on metal surfaces. It has been found that in the coverage range 0.07 < θ < 0.58, ordered Dy superstructures formed and observed at T < 400 K are irreversibly destroyed by annealing to higher temperatures and turn into an amorphous (glass) structure on cooling. It is supposed that this conversion is caused by the formation, at T > 400 K, of a Dy-Mo surface alloy in which the rate of Dy surface diffusion is strongly reduced in comparison with its value in the absence of alloying. As a result, the mobility of Dy adatoms becomes too low at the temperatures corresponding to the ordered equilibrium state of the surface, and this state cannot be achieved in reasonable relaxation time. This interpretation is corroborated by the experimental data on substantial suppression of surface diffusion in some coadsorbed layers. Since surface glasses contact with ordered (crystalline) substrates, their structure may have a peculiar character different from that of "conventional" metal glasses. Surface glasses can find a number of applications as rather stable systems that combine low dimensionality, specific electronic structure of their constituents and extremely high density of defects.
KW - Adsorbate structure
KW - Glass surfaces
KW - Glass transitions
KW - Kinetics of annealing
KW - LEED
KW - Surface diffusion
KW - Surface phase transitions
KW - Surface structure
KW - Work function measurements
UR - http://www.scopus.com/inward/record.url?scp=33646412851&partnerID=8YFLogxK
U2 - 10.1016/j.susc.2005.11.040
DO - 10.1016/j.susc.2005.11.040
M3 - Article
AN - SCOPUS:33646412851
VL - 600
SP - 1566
EP - 1573
JO - Surface Science
JF - Surface Science
SN - 0039-6028
IS - 8
ER -