From: hackbard Date: Sat, 12 Jun 2010 19:18:28 +0000 (+0200) Subject: start with simulation techniques X-Git-Url: https://hackdaworld.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6cc48aedc3767d0508e6f2aec1c3b504e362c337;p=lectures%2Flatex.git start with simulation techniques --- diff --git a/posic/talks/seminar_2010.tex b/posic/talks/seminar_2010.tex index 67de04d..81a6c57 100644 --- a/posic/talks/seminar_2010.tex +++ b/posic/talks/seminar_2010.tex @@ -182,7 +182,8 @@ \item Density functional theory (DFT) calculations \end{itemize} \item C and Si self-interstitial point defects in silicon - \item Precipitation simulations + \item Silicon carbide precipitation simulations + \item Investigation of a silicon carbide precipitate in silicon \item Summary / Conclusion / Outlook \end{itemize} @@ -343,7 +344,7 @@ Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\ \end{minipage} \begin{minipage}{6.3cm} \begin{center} - {\color{blue}\bf\normalsize + {\color{blue} Precipitation mechanism not yet fully understood! } \renewcommand\labelitemi{$\Rightarrow$} @@ -430,10 +431,63 @@ Thermal conductivity [W/cmK] & 5.0 & 4.9 & 4.9 & 1.5 & 1.3 & 22 \\ \psline[linewidth=4pt]{->}(8.5,2)(9.0,2) \psellipse[linecolor=blue](11.5,5.8)(0.3,0.5) \rput{-20}{\psellipse[linecolor=blue](3.3,8.1)(0.3,0.5)} -%\rput{-20}{\psellipse[linecolor=blue](6,6.5)(0.3,0.5)} \psline[linewidth=4pt]{->}(4.0,2)(4.5,2) \end{pspicture} \end{slide} +\begin{slide} + + {\large\bf + Basics of molecular dynamics (MD) simulations + } + + \vspace{12pt} + + \small + + {\bf MD basics:} + \begin{itemize} + \item Microscopic description of N particle system + \item Analytical interaction potential + \item Numerical integration using Newtons equation of motion\\ + as a propagation rule in 6N-dimensional phase space + \item Observables obtained by time and/or ensemble averages + \end{itemize} + {\bf Details of the simulation:} + \begin{itemize} + \item Integration: Velocity Verlet, timestep: $1\text{ fs}$ + \item Ensemble: NpT (isothermal-isobaric) + \begin{itemize} + \item Berendsen thermostat: + $\tau_{\text{T}}=100\text{ fs}$ + \item Berendsen barostat:\\ + $\tau_{\text{P}}=100\text{ fs}$, + $\beta^{-1}=100\text{ GPa}$ + \end{itemize} + \item Potential: Tersoff-like bond order potential + \vspace*{12pt} + \[ + E = \frac{1}{2} \sum_{i \neq j} \pot_{ij}, \quad + \pot_{ij} = f_C(r_{ij}) \left[ f_R(r_{ij}) + b_{ij} f_A(r_{ij}) \right] + \] + \end{itemize} + + \begin{picture}(0,0)(-230,-30) + \includegraphics[width=5cm]{tersoff_angle.eps} + \end{picture} + +\end{slide} + +\begin{slide} + + {\large\bf + Basics of density functional theory (DFT) calculations + } + + \small + +\end{slide} + + \end{document}