> that compare with taking the energies of each defect in a
> supercell.
-We would like to remind the referee that the properties of isolated,
-non-intertacting defects were modeled in separate simulation runs. It
-is not our purpose to separate defects by a large distance in order to
-approximate the situation of isolated defects. We are rather
-interested in interacting defects. However, we did find that for
-increasing defect distances, configurations appear, which converge to
-the energetics of two isolated defects. This is indicated by the
-(absolute value of the) binding energy, which is approaching zero with
-increasing distance. From this, we conclude a decrease in
-interaction, which is already observable for defect separation
-distances accessible in our simulations. Combinations of defects with
-similar distances were already successfully modeled in a supercell
-containing 216 atoms as described in PRB 66, 195214 (2002).
+The calculations criticized by the referee did not aim at the
+properties of isolated, non-intertacting defects, but rather at the
+defect-defect interaction. Single defects were modeled in separate
+simulation runs. However, we did find that for increasing defect
+distances, configurations appear, which converge to the energetics of
+two isolated defects. This is indicated by the (absolute value of the)
+binding energy, which is approaching zero with increasing distance.
+From this, we conclude a decrease in interaction, which is already
+observable for defect separation distances accessible in our
+simulations. Combinations of defects with similar distances were
+already successfully modeled in a supercell containing 216 atoms as
+described in PRB 66, 195214 (2002).
+
+% We would like to remind the referee that the properties of isolated,
+% non-intertacting defects were modeled in separate simulation runs. It
+% is not our purpose to separate defects by a large distance in order to
+% approximate the situation of isolated defects. We are rather
+% interested in interacting defects. However, we did find that for
+% increasing defect distances, configurations appear, which converge to
+% the energetics of two isolated defects. This is indicated by the
+% (absolute value of the) binding energy, which is approaching zero with
+% increasing distance. From this, we conclude a decrease in
+% interaction, which is already observable for defect separation
+% distances accessible in our simulations. Combinations of defects with
+% similar distances were already successfully modeled in a supercell
+% containing 216 atoms as described in PRB 66, 195214 (2002).
An explanation of the binding energy and the relation to the
interaction of defects was added (Change 8).
> are seen for constant volume calculations (on a few simple
> examples, say)?
-Differences are supposed to be negligible small since only small
-changes in volume are detected. However, in experiment, substrate
-swelling is observed. Thus, to allow for full relaxation, simulations
-were performed in the NpT ensemble. However, for the above-mentioned
-reason, no fundamental differences are expected for single defect
-configurations in the canonical and isothermal-isobaric ensemble with
-respect to energy.
+% Differences are supposed to be negligible small since only small
+% changes in volume are detected. However, in experiment, substrate
+% swelling is observed. Thus, to allow for full relaxation, simulations
+% were performed in the NpT ensemble. However, for the above-mentioned
+% reason, no fundamental differences are expected for single defect
+% configurations in the canonical and isothermal-isobaric ensemble with
+% respect to energy.
+
+In experiment, substrate swelling is observed for high-dose carbon
+implantation into silicon. Indeed, for a single defect, the change in
+volume is less than 0.2% in simulation. Due to this, results of single
+defects within an isothermal-isobaric simulation are expected to not
+drastically differ to results of constant volume simulations. Based on the
+experimentally observed change in volume for high-dose carbon
+implantations, however, the respective relaxation is allowed for in
+simulation for both, single defect calulations as well as the high carbon
+concentration simulations.
A respective statement was added to the methodology section
(Change 4).
appropriately consider the overestimated barrier heights for
diffusion.
-Indeed the cut-off effect increases if the system is driven away from
-the equilibrium (such as by modeling IBS). Since this is to some
+Indeed, the cut-off effect increases if the system is driven away from
+the equilibrium, such as it is the case in IBS. Since this is to some
extent cured by increasing the simulation temperature, the work-around
is particularly helpful for short range potentials.
projects / lectures / latex.git / blobdiff