started c_i vs c_s si_i section

diff --git a/posic/publications/sic_prec.tex b/posic/publications/sic_prec.tex
index aa02bb4..eb04ca2 100644 (file)
--- a/posic/publications/sic_prec.tex
+++ b/posic/publications/sic_prec.tex
@@ -153,13 +153,24 @@ The EA potential does not reproduce the correct ground state.
 Instead the tetrahedral defect configuration is favored.
 This limitation is assumed to arise due to the cut-off.
 In the tetrahedral configuration the second neighbors are only slightly more distant than the first neighbors, which creates the particular problem.
-Indeed an increase of the cut-off results in increased values of the formation energies\cite{albe_sic_pot}, which is most significant for the terahedral configuration.
+Indeed an increase of the cut-off results in increased values of the formation energies\cite{albe_sic_pot}, which is most significant for the tetrahedral configuration.
 The same issue has already been discussed by Tersoff\cite{tersoff90} with regard to the description of the tetrahedral C defect using his potential.
 While not completely rendering impossible further, more challenging, empirical potential studies on large systems, the artifact has to be taken into account in the following investigations of defect combinations.
 %This artifact does not necessarily render impossible further challenging empirical potential studies on large systems.
 %However, it has to be taken into account in the following investigations of defect combinations.
 
-\subsection{Defect combinations}
+\subsection{Formation energies of C$_{\text{i}}$ and C$_{\text{s}}$-Si$_{\text{i}}$}
+
+As has been shown in a previous study\cite{zirkelbach10b}, the energetically most favorable configuration of C$_{\text{s}}$ and Si$_{\text{i}}$ is obtained for C$_{\text{s}}$ located at the next neighbored lattice site along the \hkl<1 1 0> bond chain of a Si$_{\text{i}}$ \hkl<1 1 0> DB.
+However the energy of formation is slightly higher than that of the C$_{\text{i}}$ \hkl<1 0 0> DB, which constitutes the ground state for a C impurity introduced into otherwise perfect c-Si.
+
+For a possible clarification of the controversial views on the participation of C$_{\text{s}}$ in the precipitation mechanism by classical potential simulations, test calculations need to ensure the proper description of the relative formation energies of combined structures of C$_{\text{s}}$ and Si$_{\text{i}}$ compared to C$_{\text{i}}$.
+This is particularly important since the energy of formation of C$_{\text{s}}$ is drastically underestimated by the EA potential.
+A possible occurence of C$_{\text{s}}$ could then be attributed to a lower energy of formation of the C$_{\text{s}}$-Si$_{\text{i}}$ combination due to the low formation energy of  C$_{\text{s}}$, which obviously is wrong.
+
+WEITER: while si 110 for qm, also tet has to be checkd as a combo with Cs.
+The results are summarized in Table.
+However, ...
 
 \subsection{Mobility}