From: hackbard Date: Sun, 26 Sep 2010 13:22:30 +0000 (+0200) Subject: discussion stuff X-Git-Url: https://hackdaworld.org/gitweb/?p=lectures%2Flatex.git;a=commitdiff_plain;h=7a410a46a51a99afb239b26d60e84cf980536c40 discussion stuff --- diff --git a/posic/publications/sic_prec.tex b/posic/publications/sic_prec.tex index 860fe77..7d481b5 100644 --- a/posic/publications/sic_prec.tex +++ b/posic/publications/sic_prec.tex @@ -353,14 +353,16 @@ It turned out that the EA potential still favors a C$_{\text{i}}$ \hkl<1 0 0> DB MD simulations at temperatures used in IBS resulted in structures that were dominated by the C$_{\text{i}}$ \hkl<1 0 0> DB and its combinations if C is inserted into the total volume. Incoorporation into volmes $V_2$ and $V_3$ led to an amorphous SiC-like structure within the respective volume. -To ensure correct diffusion behavior simulations at elevated temperatures have been performed. -Although ... +To compensate overestimated diffusion barriers we performed simulations at elevated temperatures. +TOOD: High C conc simulations ... then low: +Time scales are still too low to observe C agglomeration sufficient for SiC precipitation, which is attributed to the slow phase space propagation inherent to MD in general. +However, we observed a phase tranisiton of the C$_{\text{i}}$-dominated into a clearly C$_{\text{s}}$-dominated structure. +The amount of substitutionally occupied C atoms increases with increasing temperature. +Entropic contributions are assumed to be responsible for these structures that deviate from the ground state at 0 K. +Indeed, in a previous ab initio MD simulation\cite{zirkelbach10b} performed at \unit[900]{$^{\text{C}}$} we observed the departing of a Si$_{\text{i}}$ \hkl<1 1 0> DB located next to a C$_{\text{s}}$ atom instead of a recombination into the ground state configuration, i.e. a C$_{\text{i}}$ \hkl<1 0 0> DB. -entropic contribution. -as in \cite{zirkelbach10b}, next neighbored Cs and Sii did not recombine, but departed from each other. - -Sii stress compensation ... Thus, we prpopose (support) the follwing model ... +Sii stress compensation and vehicle Concluded that C sub is very probable ... Alignment lost, successive substitution more probable to end up with topotactic 3C-SiC.