X-Git-Url: https://hackdaworld.org/gitweb/?a=blobdiff_plain;f=posic%2Ftalks%2Fupb-ua-xc.tex;h=524ec2bd4daf1fbc1144d24fe291304a747ca2c1;hb=a0ad462d8874ee78d823284d8175eb22c1f35d81;hp=04192521224a543fbf628c5741fdbf4d2ac86d69;hpb=162206abf206f18e6d23e452b95a903bd2aafae1;p=lectures%2Flatex.git diff --git a/posic/talks/upb-ua-xc.tex b/posic/talks/upb-ua-xc.tex index 0419252..524ec2b 100644 --- a/posic/talks/upb-ua-xc.tex +++ b/posic/talks/upb-ua-xc.tex @@ -675,51 +675,152 @@ POTIM = 0.1 \end{itemize} \vspace*{0.2cm} \underline{Param 2}\\ - After talking to the pros! Used for 'large' simulations. + After talking to the pros! \begin{itemize} \item $\Gamma$-point only \item $E_{\text{cut-off}}=xyz\text{ eV}$ \item Gaussian smearing ($\sigma=0.05$) \item Use symmetry - \item Real space projection (Auto, Medium) + \item Real space projection (Auto, Medium) for 'large' simulations \end{itemize} \vspace*{0.2cm} {\color{blue} In both parameter sets the ultra soft pseudo potential method - as well as the projector augmented wave method is used! + as well as the projector augmented wave method is used with both, + the LDA and GGA exchange correlation potential! } \end{slide} \begin{slide} + \footnotesize + {\large\bf Properties of Si, C and SiC using the new parameters\\ } - $2\times 2\times 2$ Type 2 supercell, Param 1\\[0.2cm] + $2\times 2\times 2$ Type 2 supercell, Param 1, LDA, US PP\\[0.2cm] \begin{tabular}{|l|l|l|l|} \hline & c-Si & c-C (diamond) & 3C-SiC \\ \hline - Lattice constant [\AA] & 5.389 & 3.527 & \\ - Expt. [\AA] & 5.429 & 3.567 & \\ - Error [\%] & {\color{green}0.7} & 1.1 & \\ + Lattice constant [\AA] & 5.389 & 3.527 & 4.319 \\ + Expt. [\AA] & 5.429 & 3.567 & 4.359 \\ + Error [\%] & {\color{green}0.7} & {\color{green}1.1} & {\color{green}0.9} \\ \hline - Cohesive energy [eV] & -4.674 & -8.812 & \\ - Expt. [eV] & -4.63 & -7.374 & \\ - Error [\%] & {\color{green}1.0} & {\color{red}19.5} & \\ + Cohesive energy [eV] & -5.277 & -8.812 & -7.318 \\ + Expt. [eV] & -4.63 & -7.374 & -6.340 \\ + Error [\%] & {\color{red}14.0} & {\color{red}19.5} & {\color{red}15.4} \\ \hline \end{tabular}\\ + \begin{minipage}{10cm} + $2\times 2\times 2$ Type 2 supercell, 3C-SiC, Param 1\\[0.2cm] + \begin{tabular}{|l|l|l|l|} + \hline + & {\color{magenta}US PP, GGA} & PAW, LDA & PAW, GGA \\ + \hline + Lattice constant [\AA] & 4.370 & 4.330 & 4.379 \\ + Error [\%] & {\color{green}0.3} & {\color{green}0.7} & {\color{green}0.5} \\ + \hline + Cohesive energy [eV] & -6.426 & -7.371 & -6.491 \\ + Error [\%] & {\color{green}1.4} & {\color{red}16.3} & {\color{green}2.4} \\ + \hline + \end{tabular} + \end{minipage} + \begin{minipage}{3cm} + US PP, GGA\\[0.2cm] + \begin{tabular}{|l|l|} + \hline + c-Si & c-C \\ + \hline + 5.455 & 3.567 \\ + {\color{green}0.5} & {\color{green}0.01} \\ + \hline + -4.591 & -7.703 \\ + {\color{green}0.8} & {\color{orange}4.5} \\ + \hline + \end{tabular} + \end{minipage} + \end{slide} \begin{slide} {\large\bf - C interstitial in c-Si + Energy cut-off for $\Gamma$-point only caclulations } - + $2\times 2\times 2$ Type 2 supercell, Param 2, US PP, LDA, 3C-SiC\\[0.2cm] + \includegraphics[width=5.5cm]{sic_32pc_gamma_cutoff.ps} + \includegraphics[width=5.5cm]{sic_32pc_gamma_cutoff_lc.ps}\\ + $\Rightarrow$ Use 300 eV as energy cut-off?\\[0.2cm] + $2\times 2\times 2$ Type 2 supercell, Param 2, 300 eV, US PP, GGA\\[0.2cm] + \small + \begin{minipage}{10cm} + \begin{tabular}{|l|l|l|l|} + \hline + & c-Si & c-C (diamond) & 3C-SiC \\ + \hline + Lattice constant [\AA] & 5.470 & 3.569 & 4.364 \\ + Error [\%] & {\color{green}0.8} & {\color{green}0.1} & {\color{green}0.1} \\ + \hline + Cohesive energy [eV] & -4.488 & -7.612 & -6.359 \\ + Error [\%] & {\color{orange}3.1} & {\color{orange}3.2} & {\color{green}0.3} \\ + \hline + \end{tabular} + \end{minipage} + \begin{minipage}{2cm} + {\LARGE + ${\color{green}\surd}$ + } + \end{minipage} + +\end{slide} + +\begin{slide} + + {\large\bf + C 100 interstitial migration along 110 in c-Si (Albe potential) + } + + \small + + \begin{minipage}[t]{4.2cm} + \underline{Starting configuration}\\ + \includegraphics[width=4cm]{c_100_mig/start.eps} + \end{minipage} + \begin{minipage}[t]{4.0cm} + \vspace*{0.8cm} + $\Delta x=\frac{1}{4}a_{\text{Si}}=1.357\text{ \AA}$\\ + $\Delta y=\frac{1}{4}a_{\text{Si}}=1.357\text{ \AA}$\\ + $\Delta z=0.325\text{ \AA}$\\ + \end{minipage} + \begin{minipage}[t]{4.2cm} + \underline{{\bf Expected} final configuration}\\ + \includegraphics[width=4cm]{c_100_mig/final.eps}\\ + \end{minipage} + \begin{minipage}{6cm} + \begin{itemize} + \item Fix border atoms of the simulation cell + \item Constraints and displacement of the C atom: + \begin{itemize} + \item along {\color{green}110 direction}\\ + displaced by {\color{green} $\frac{1}{10}(\Delta x,\Delta y)$} + \item C atom {\color{red}entirely fixed in position}\\ + displaced by + {\color{red}$\frac{1}{10}(\Delta x,\Delta y,\Delta z)$} + \end{itemize} + \end{itemize} + {\bf\color{blue}Expected configuration not obtained!} + \end{minipage} + \begin{minipage}{0.5cm} + \hfill + \end{minipage} + \begin{minipage}{6cm} + \includegraphics[width=6.0cm]{c_100_110mig_01_albe.ps} + \end{minipage} + \end{slide}