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# Line 33 | Line 33 | In a recent series of experiments, Li, Lieberman, and
33   \section{Introduction}
34  
35   In a recent series of experiments, Li, Lieberman, and Hill found some
36 < remarkable differences in the coverage of Gold (111) surfaces by a
36 > remarkable differences in the coverage of Au (111) surfaces by a
37   related set of silicon phthalocyanines.\cite{Li2001} The molecules
38   come in two basic varieties, the ``octopus,'' which has eight thiol
39   groups distributed around the edge of the molecule, and the
# Line 103 | Line 103 | increasing particle anisotropy once the length-to-brea
103   (4\%) initial rise in $\theta_{J}$ as a function of particle
104   anisotropy.  However, the jamming limit {\it decreases} with
105   increasing particle anisotropy once the length-to-breadth ratio rises
106 < above 2. I.e. ellipsoids landing randomly on a surface will, in
106 > above 2, \emph{i.e.}~ellipsoids landing randomly on a surface will, in
107   general, cover a smaller surface area than disks. Randomly thrown thin
108   lines cover an even smaller area.\cite{Viot1992b}
109  
110   How, then, can one explain a near-monolayer coverage by the umbrella
111 < molecules?  There are really two approaches, one static and one
112 < dynamic.  In this paper, we present a static RSA model with {\em
111 > molecules? In this paper, we present a static RSA model with {\em
112   tilted} disks that allows near-monolayer coverage and which can
113   explain the differences in coverage between the octopus and umbrella.
114   In section \ref{rsaSec:model} we outline the model for the two adsorbing
# Line 169 | Line 168 | underlying gold hexagonal closed packed (hcp), lattice
168   the thiol groups.  In the continuum case, the landers could attach
169   anywhere on the surface.  For the lattice-based RSA simulations, an
170   underlying gold hexagonal closed packed (hcp), lattice was employed.
171 < The thiols attach at the interstitial locations between three gold
171 > The thiols attach at the three-fold hollow locations between three gold
172   atoms on the Au (111) surface,\cite{Li2001} giving a trigonal (i.e.
173   graphitic) underlying lattice for the RSA simulations that is
174   illustrated in Fig. \ref{rsaFig:hcp_lattice}.  The hcp nearest neighbor
# Line 181 | Line 180 | $\hat{x}$ and $\hat{y}$ directions for the simulation.
180   \begin{figure}
181   \centering
182   \includegraphics[width=\linewidth]{hcp_lattice.eps}
183 < \caption[Depiction of the hcp interstitial sites]{The model thiol groups attach at the interstitial sites in
183 > \caption[Depiction of the hcp three-fold hollow sites]{The model thiol groups attach at the three-fold hollow sites in
184   the Au (111) surface.  These sites are arranged in a graphitic
185   trigonal lattice.}
186   \label{rsaFig:hcp_lattice}
# Line 219 | Line 218 | intersection along the line were checked to insure seq
218   was then checked for intersection with both of the umbrella tops.  If
219   the line did indeed intersect the tops, then the points of
220   intersection along the line were checked to insure sequential
221 < intersection of the two tops. ie. The line most enter then leave the
221 > intersection of the two tops. ie. The line must enter then leave the
222   first top before it can enter and leave the second top.  These series
223   of tests were demanding of computational resources, and were therefore
224   only attempted if the original handle - projection overlap test had
# Line 232 | Line 231 | plane was used to pick an attachment point from the un
231  
232   For the on-lattice simulations, the initially chosen location on the
233   plane was used to pick an attachment point from the underlying
234 < lattice.  I.e. if the initial position and orientation placed one of
234 > lattice. Meaning, if the initial position and orientation placed one of
235   the thiol legs within a small distance ($\epsilon = 0.1 \mbox{\AA}$)
236   of one of the interstitial attachment points, the lander was moved so
237   that the thiol leg was directly over the lattice point before checking
# Line 250 | Line 249 | multiplying the number of succesfully landed particles
249   umbrella molecule simulation, and the octopus model simulation.  In
250   the case of the umbrella molecule, the surface coverage was tracked by
251   multiplying the number of succesfully landed particles by the area of
252 < its circular top.  This number was then divided by the total surfacew
252 > its circular top.  This number was then divided by the total surface
253   area of the plane, to obtain the fractional coverage.  In the case of
254   the umbrella molecule, a scanning probe algorithm was used.  Here, a
255   $1\mbox{\AA} \times 1\mbox{\AA}$ probe was scanned along the surface,
# Line 274 | Line 273 | Once the system is constrained by the underlying latti
273   larger gold surface.
274  
275   Once the system is constrained by the underlying lattice, $\theta_{J}$
276 < drops to 0.5378, showing that the lattice has an almost
276 > drops to 0.5378, showing that the lattice has an
277   inconsequential effect on the jamming limit.  If the spacing between
278   the interstitial sites were closer to the radius of the landing
279   particles, we would expect a larger effect, but in this case, the
# Line 379 | Line 378 | Table \ref{rsaTab:coverage}.
378   Table \ref{rsaTab:coverage}.
379  
380   \begin{table}
381 < \caption[RSA experimental comparison]{Ratio of Monolayer Sulfur atoms to Gold surface atoms}
381 > \caption{RATIO OF MONOLAYER SULFUR ATOMS TO GOLD SURFACE ATOMS}
382   \label{rsaTab:coverage}
383   \begin{center}
384   \begin{tabular}{|l|l|l|}

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