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\subsection{Construction and Equilibration of 557 Metal interfaces} |
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Our model systems are composed of approximately 4000 metal atoms cut along the 557 plane so that they are periodic in the \it{x} and \it{y} directions exposing the 557 plane in the \it{z} direction. Runs at various temperatures ranging from 300~K to 1200~K were started with the intent of viewing relative stability of the surface when CO was not present in the system. Owing to the different melting points (1337~K for Au and 2045~K for Pt), the bare crystal systems were initially run in the Canonical ensemble for at 800~K and 1000~K respectively for 100 ps. Various amounts of CO were placed in the vacuum portion which upon full adsorption to the surface corresponded to 5\%, 25\%, 33\%, and 50\% coverages. These systems were again allowed to reach thermal equilibrium before being run in the micro canonical ensemble. All of the systems examined were run for at least 40 ns. A subset that were undergoing interesting effects have been allowed to continue running with one system approaching 200 ns.em |
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Our model systems are composed of approximately 4000 metal atoms |
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cut along the 557 plane so that they are periodic in the {\it x} and {\it y} |
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> |
directions exposing the 557 plane in the {\it z} direction. Runs at various |
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> |
temperatures ranging from 300~K to 1200~K were started with the intent |
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of viewing relative stability of the surface when CO was not present in the |
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system. Owing to the different melting points (1337~K for Au and 2045~K for Pt), |
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> |
the bare crystal systems were initially run in the Canonical ensemble at |
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> |
800~K and 1000~K respectively for 100 ps. Various amounts of CO were |
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placed in the vacuum region, which upon full adsorption to the surface |
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> |
corresponded to 5\%, 25\%, 33\%, and 50\% coverages. These systems |
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> |
were again allowed to reach thermal equilibrium before being run in the |
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microcanonical ensemble. All of the systems examined in this work were |
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run for at least 40 ns. A subset that were undergoing interesting effects |
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> |
have been allowed to continue running with one system approaching 200 ns. |
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All simulations were run using the open source molecular dynamics package, OpenMD. \cite{Ewald, OOPSE} |
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