362 |
|
{\it et al.}\cite{Tao:2010}, who also showed that the addition of CO |
363 |
|
leads to a reversal in stability. |
364 |
|
|
365 |
< |
The DFT calculations suggest an increased stability of 0.1 kcal/mol |
366 |
< |
per Pt atom, while our force field gives an approximately 0.4 kcal/mol |
367 |
< |
increase in stability per Pt atom. |
365 |
> |
The DFT calculations suggest an increased stability of 0.08 kcal/mol |
366 |
> |
(0.7128 eV) per Pt atom for going from the single to double step |
367 |
> |
structure in the presence of carbon monoxide. |
368 |
|
|
369 |
|
The gold systems show much smaller energy differences between the |
370 |
|
single and double layers. The weaker binding of CO to Au is evidenced |
371 |
|
by the much smaller change in relative energy between the structures |
372 |
|
when carbon monoxide is present. Additionally, as CO-Au binding is |
373 |
< |
much weaker, it would be unlikely that CO would approach the 50\% |
374 |
< |
coverage levels operating temperatures. |
373 |
> |
much weaker than CO-Pt, it would be unlikely that CO would approach |
374 |
> |
the 50\% coverage levels operating temperatures for the gold surfaces. |
375 |
|
|
376 |
|
%Table of single step double step calculations |
377 |
|
\begin{table}[H] |