started combo of defects
authorhackbard <hackbard@sage.physik.uni-augsburg.de>
Mon, 15 Feb 2010 19:28:10 +0000 (20:28 +0100)
committerhackbard <hackbard@sage.physik.uni-augsburg.de>
Mon, 15 Feb 2010 19:28:10 +0000 (20:28 +0100)
posic/thesis/defects.tex

index 2206dee..b421b3d 100644 (file)
@@ -568,7 +568,7 @@ Todo: To refine the migration barrier one has to find the saddle point structure
 
 \begin{figure}[h]
 \begin{center}
-\includegraphics[width=13cm]{im_00-1_nosym_sp_fullct_thesis.ps}\\[0.5cm]
+\includegraphics[width=13cm]{im_00-1_nosym_sp_fullct_thesis.ps}\\[1.5cm]
 \begin{picture}(0,0)(150,0)
 \includegraphics[width=2.5cm]{vasp_mig/00-1.eps}
 \end{picture}
@@ -595,7 +595,7 @@ In a second process 0.25 eV of energy are needed for the system to revert into a
 
 \begin{figure}[h]
 \begin{center}
-\includegraphics[width=13cm]{vasp_mig/00-1_0-10_nosym_sp_fullct.ps}\\[0.5cm]
+\includegraphics[width=13cm]{vasp_mig/00-1_0-10_nosym_sp_fullct.ps}\\[1.6cm]
 \begin{picture}(0,0)(140,0)
 \includegraphics[width=2.5cm]{vasp_mig/00-1_a.eps}
 \end{picture}
@@ -620,7 +620,7 @@ The resulting migration barrier of approximately 0.9 eV is very close to the exp
 
 \begin{figure}[h]
 \begin{center}
-\includegraphics[width=13cm]{vasp_mig/00-1_ip0-10_nosym_sp_fullct.ps}\\[0.5cm]
+\includegraphics[width=13cm]{vasp_mig/00-1_ip0-10_nosym_sp_fullct.ps}\\[1.8cm]
 \begin{picture}(0,0)(140,0)
 \includegraphics[width=2.2cm]{vasp_mig/00-1_b.eps}
 \end{picture}
@@ -652,4 +652,40 @@ In addition the bond-ceneterd configuration, for which spin polarized calculatio
 
 \section{Combination of point defects}
 
+\begin{figure}[h]
+\begin{center}
+\begin{minipage}{7.5cm}
+\includegraphics[width=7cm]{comb_pos.eps}
+\end{minipage}
+\begin{minipage}{6.0cm}
+\underline{Positions given in $a_{\text{Si}}$}\\[0.3cm]
+Initial interstitial: $\frac{1}{4}\hkl<1 1 1>$\\
+Relative silicon neighbour positions:
+\begin{enumerate}
+ \item $\frac{1}{4}\hkl<1 1 -1>$, $\frac{1}{4}\hkl<-1 -1 -1>$ ()
+ \item $\frac{1}{2}\hkl<1 0 1>$, $\frac{1}{2}\hkl<0 1 -1>$,\\[0.2cm]
+       $\frac{1}{2}\hkl<0 -1 -1>$, $\frac{1}{2}\hkl<-1 0 -1>$
+ \item $\frac{1}{4}\hkl<1 -1 1>$, $\frac{1}{4}\hkl<-1 1 1>$
+ \item $\frac{1}{4}\hkl<-1 1 -3>$, $\frac{1}{4}\hkl<1 -1 -3>$
+ \item $\frac{1}{2}\hkl<-1 -1 0>$, $\frac{1}{2}\hkl<1 1 0>$
+\end{enumerate}
+\end{minipage}\\
+\begin{picture}(0,0)(190,20)
+\includegraphics[width=2.3cm]{100_arrow.eps}
+\end{picture}
+\begin{picture}(0,0)(220,0)
+\includegraphics[height=2.2cm]{001_arrow.eps}
+\end{picture}
+\end{center}
+\caption[\hkl<0 0 -1> dumbbell interstitial defect and positions of next neighboured silicon atoms used for the second defect.]{\hkl<0 0 -1> dumbbell interstitial defect and positions of next neighboured silicon atoms used for the second defect. Two possibilities exist for red numbered atoms and four possibilities exist for blue numbered atoms.}
+\label{fig:defects:pos_of_comb}
+\end{figure}
+The structural and energetic properties of combinations of point defects are investigated in the following.
+The focus is on combinations of the \hkl<0 0 -1> dumbbell interstitial with a second defect.
+The second defect is either another \hkl<1 0 0>-type interstitial occupying different orientations, a vacany or a substitutional carbon atom.
+Several distances of the two defects are examined.
+Investigations are restricted to quantum-mechanical calculations.
+Figure \ref{fig:defects:pos_of_comb} shows the initial \hkl<0 0 -1> dumbbell interstitial defect and the positions of the next neighboured silicon atoms used for the second defect.
+
+