58 |
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Notre Dame, Indiana 46556} |
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%Date |
61 |
< |
\date{Mar 4, 2013} |
61 |
> |
\date{Mar 5, 2013} |
62 |
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%authors |
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to explore possible mechanisms for any observed reconstructions and their dynamics. |
74 |
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The metal-CO interactions were parameterized as part of this |
75 |
|
work so that an efficient large-scale treatment of this system could be |
76 |
< |
undertaken. The relative binding strengths of the metal-CO |
77 |
< |
interactions were found to play a large role with regards to |
76 |
> |
undertaken. The large difference in binding strengths of the metal-CO |
77 |
> |
interactions was found to play a significant role with regards to |
78 |
|
step-edge stability and adatom diffusion. A small correlation |
79 |
< |
between coverage and the size of the diffusion constant was |
79 |
> |
between coverage and the magnitude of the diffusion constant was |
80 |
|
also determined. An in-depth examination of the energetics of CO |
81 |
|
adsorbed to the surface provides results that appear sufficient to explain the |
82 |
|
reconstructions observed on the Pt systems and the corresponding lack |
113 |
|
carbon monoxide.\cite{Tao:2010} |
114 |
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|
115 |
|
This work is an attempt to understand the mechanism and timescale for |
116 |
< |
surface restructuring using molecular simulations. Since the dynamics |
116 |
> |
surface restructuring by using molecular simulations. Since the dynamics |
117 |
|
of the process are of particular interest, we employ classical force |
118 |
|
fields that represent a compromise between chemical accuracy and the |
119 |
|
computational efficiency necessary to simulate the process of interest. |
120 |
< |
Restructuring can occur as a result of specific interactions of the |
121 |
< |
catalyst with adsorbates. In this work, two metal systems exposed |
120 |
> |
Since restructuring typically occurs as a result of specific interactions of the |
121 |
> |
catalyst with adsorbates, in this work, two metal systems exposed |
122 |
|
to carbon monoxide were examined. The Pt(557) surface has already been shown |
123 |
|
to reconstruct under certain conditions. The Au(557) surface, because |
124 |
|
of a weaker interaction with CO, is less likely to undergo this kind |
125 |
< |
of reconstruction. MORE HERE ON PT AND AU PREVIOUS WORK. |
125 |
> |
of reconstruction. |
126 |
> |
|
127 |
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|
128 |
+ |
|
129 |
|
%Platinum molecular dynamics |
130 |
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%gold molecular dynamics |
131 |
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