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\subsection{\label{sec:SSD}The {\sc DUFF} Water Models: SSD/E and SSD/RF} |
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In the interest of computational efficiency, the default solvent used |
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< |
in {\sc oopse} is the Soft Sticky Dipole (SSD) water model. SSD was |
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developed by Ichiye \emph{et al.} as a modified form of the |
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< |
hard-sphere water model proposed by Bratko, Blum, and |
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> |
by {\sc oopse} is the extended Soft Sticky Dipole (SSD/E) water |
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> |
model.\cite{Gezelter04} The original SSD was developed by Ichiye |
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> |
\emph{et al.}\cite{Ichiye96} as a modified form of the hard-sphere |
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> |
water model proposed by Bratko, Blum, and |
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Luzar.\cite{Bratko85,Bratko95} It consists of a single point dipole |
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with a Lennard-Jones core and a sticky potential that directs the |
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particles to assume the proper hydrogen bond orientation in the first |
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{\it charged} multi-point models. In the original Monte Carlo |
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simulations using this model, Ichiye {\it et al.} reported that using |
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SSD decreased computer time by a factor of 6-7 compared to other |
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models.\cite{Ichiye96} What is most impressive is that this savings |
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> |
models.\cite{Ichiye96} What is most impressive is that these savings |
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did not come at the expense of accurate depiction of the liquid state |
| 338 |
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properties. Indeed, SSD maintains reasonable agreement with the Soper |
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data for the structural features of liquid |
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> |
diffraction data for the structural features of liquid |
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water.\cite{Soper86,Ichiye96} Additionally, the dynamical properties |
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exhibited by SSD agree with experiment better than those of more |
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computationally expensive models (like TIP3P and |
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Recent constant pressure simulations revealed issues in the original |
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SSD model that led to lower than expected densities at all target |
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pressures.\cite{Ichiye03,Gezelter04} The default model in {\sc oopse} |
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is SSD/E, a density corrected derivative of SSD that exhibits improved |
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< |
liquid structure and transport behavior. If the use of a reaction |
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< |
field long-range interaction correction is desired, it is recommended |
| 353 |
< |
that the parameters be modified to those of the SSD/RF model. Solvent |
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< |
parameters can be easily modified in an accompanying {\sc BASS} file |
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< |
as illustrated in the scheme below. A table of the parameter values |
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< |
and the drawbacks and benefits of the different density corrected SSD |
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< |
models can be found in reference \ref{Gezelter04}. |
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> |
is therefore SSD/E, a density corrected derivative of SSD that |
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> |
exhibits improved liquid structure and transport behavior. If the use |
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> |
of a reaction field long-range interaction correction is desired, it |
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> |
is recommended that the parameters be modified to those of the SSD/RF |
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> |
model. Solvent parameters can be easily modified in an accompanying |
| 355 |
> |
{\sc BASS} file as illustrated in the scheme below. A table of the |
| 356 |
> |
parameter values and the drawbacks and benefits of the different |
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> |
density corrected SSD models can be found in reference |
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> |
\ref{Gezelter04}. |
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|
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!!!Place a {\sc BASS} scheme showing SSD parameters around here!!! |
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|
