> resubmit, please include a summary of the changes made, and a detailed
> response to all recommendations and criticisms.
-We decided to follow your's and the referee's suggestion to merge the
+We decided to follow yours and the referee's suggestion to merge the
two manuscripts into a single comprehensive manuscript.
Please find below the summary of changes and a detailed response to
the recommendations of the referee.
Most of the criticism is pasted from the previous review justified by
-the accusation that we did ignore or not adequatley answered them.
-However, we did comment on every single issue and a more adequate
+the statement that we did ignore or not adequatley respond to it.
+However, we commented on every single issue and a more adequate
answer is hindered if the referee does not specify the respective
-points of criticism. Thus, some responses are identical to these
-included of our previous answer.
+points of criticism. Thus, some part of the response might be
+identical to our previous one.
Sincerely,
--------------- Response to recommendations ----------------
+TODO: add changes applied due to criticism ...
+
> I am not happy with these two papers for a multitude of reasons,
> and I recommend that the authors rewrite them as a single longer
> paper, to eliminate the criticism of serial publication. I do not
> calculations, and one for the MD this is not how I suggest you
> do it, though.
-We now combined the two manuscripts into a single comprehensive one.
+We now combined the two manuscripts to a single comprehensive one.
> do it, though. First, though, the following issues should be
> addressed (some are simply pasted from my previous reviews, where
> conclusions on which structure or migration routes are most
> likely start to look rather less certain.
-Although differences of 0.2 eV in DFT calculations would generally be
-acknowledged to be insignificant when being compared to experimental
-results or data of other ab initio studies, these differences are
-considered to be reliable when comparing results, i.e. differences in
-energy, of a systematic study among each other. This is commonly done
-as can be seen in a great deal of literature, some of which is cited
-in the section of the present manuscript that investigates defect
-structures and formation energies. Very often differences less than
-0.2 eV are obtained and conclusions on the stability of a particular
-structure are derived.
+In literature, very often, differences less than 0.2 eV are obtained
+in DFT studies and respective conclusions are derived. For instance,
+differences in the energy of formation ranging from 0.05 - 0.12 eV are
+considered significant enough to conclude on the energetically most
+favorable intrinsic defect configurations in Si (PRB 68, 235205
+(2003); PRL 83, 2351 (1999)). This is due to the fact that existing
+errors are most probably of the systematic rather than the random
+type. The error in the estimate of the cohesive energy is canceled out
+since it is likewise wrong in the defect as in the bulk configuration,
+which are substracted in the expression of the defect formation
+energy. Even if the defect formation energy is overestimated due to a
+too small size of the supercell resulting in a non-zero interaction of
+the defect with its images, this is likewise true for other defects.
+Although the actual value might be wrong, observed differences in
+energy, thus, allow to draw conlcusions on the stability of defect
+configurations. This is also valid for diffusion barriers, which are
+given by differences in energy of different structures.
+In fact, differences of 0.2 eV in DFT calculations are considered
+insignificant when being compared to experimental results or data of
+other ab initio studies. However, the observed differences in energy
+within our systematic DFT study are considered reliable.
> 2. Why is 216 atoms a large enough supercell many defect
> properties are known to converge very slowly with supercell size.
+
+Of course, choosing a supercell containing 216 atoms constitutes a
+tradeoff. It is considered the optimal choice with respect to
+computational efficiency and accuracy.
+
+We would like to point out that, both, single defects as well as
+combinations of two defects were investigated in such supercells in
+successive calculations.
+
+For single defects, the size of the supercell should be sufficient.
+This is shown in PRB 58, 1318 (1998) predicting convergence of the
+vacancy in silicon - the defect assumed to be most critical due to
+the flatness of the total energy surface as a function of the ionic
+coordinates - for supercells containing more than 128 atomic sites,
+where the defect formation energy is already well estimated using
+smaller supercells of 64 atomic sites. Thus, convergence of the
+formation energies of single defects with respect to the size of the
+supercell is assumed.
+
> They appear to be separating defects by as large a distance as
> can be accommodated in the supercell to approximate the isolated
> defects, but then they are only separated by a few lattice
> that compare with taking the energies of each defect in a
> supercell.
-Choosing a 216 atom supercell constitutes a tradeoff, of course.
-However, it is considered the optimal choice with respect to both,
-computing time and accuracy of the results.
-
-The convergence of the formation energies of single defects with
-respect to the size of the supercell is ensured. For this reason, they
-are referred to as single isolated defects.
-
-It is not our purpose to separate defects by a large distance in order
-to approximate the situation of isolated defects. However, we find
-that for increasing defect distance 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. This is stated now more
-clearly in section II of the revised manuscript. (-> Change 6)
+Again, we would like to point out that it is not our purpose to
+separate defects by a large distance in order to approximate the
+situation of isolated defects. However, we 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.
Nevertheless, the focus is on closely neighbored, interacting defects
(for which an interaction with their own image is, therefore, supposed
-to be negligible, too). At no time, our aim was to investigate single
-isolated defect structures and their properties by increasing the
-separation distance of two defects belonging to a a defect
-combination.
-
-A note is added to let the reader know that convergence with respect
-to the system size is ensured. (-> Change 2)
+to be negligible, too). In fact, combinations of defects exhibiting
+equivalent distances were successfully modeled in a supercell
+containing 216 atoms in PRB 66, 195214 (2002). At no time, our aim was
+to investigate single isolated defect structures and their properties
+by a structure with increased separation distance of the two defects.
> 3. Constant pressure solves some problems, but creates others
> is it really a sensible model of implantation? What differences
assumed that there is no fundamental difference between calculations
in the canonical and isothermal-isobaric ensemble.
-Constant volume calculations were not performed and, thus, we cannot
-provide concrete differences.
-
-The fact that there are only small changes in volume is added to the
-methodology section. (-> Change 3)
-
> 4. What method do they use to determine migration paths? How can
> they convince us that the calculations cover all possible
> migrations paths that is, the paths they calculate are really
> need a critical scrutiny, which I am not very convinced by in
> this case.
+TODO: add idea that elevated temperatures are considered necessary to
+deviate the system out of equilibrium, as assumed to be the case in IBS
+
+you can always add constant to energy.
+formation energies are not overestimated
+just the migration barriers are
+to increase probability of transitions, temperature is increased
+occupation of energetically more unfavorable states likewise increased
+indeed, sub conf, which is slightly higher than c-si DB, is increased
+comparing with experimental findings that suggest c sub for higher
+temperatures gives rise to the conclusion that the increased
+temperatures are needed to deviate the system out of the ground state!
+
There is not necessarily a correlation of cohesive energies or defect
formation energies with activation energies for migration. Cohesive
energies are most often well described by the classical potentials
distance, which according to the universal energy relation would
usually correspond to a much larger distance, unphysical high forces
between two neighbored atoms arise. This is explained in detail in the
-study of Mattoni et. al. (Phys. Rev. B 76, 224103 (2007)).
+study of Mattoni et. al. (PRB 76, 224103 (2007)).
Since most of the defect structures show atomic distances below the
critical distance, for which the cut-off function is taking effect,
The arguments discussed above are now explained in more detail in the
revised version of our work. (-> Change 1, Change 2)
+
+
+--------------- Summary of changes ----------------
+
+
+
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