Differences

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--- exercises:2016_uzh_cmest:calculating_pdos [2016/10/31 05:40] – tmueller
+++ exercises:2016_uzh_cmest:calculating_pdos [2020/08/21 10:15] (current) – external edit 127.0.0.1
@@ Line 105: / Line 105: @@
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-The columns correspond to the orbitals present in the basis set (hence //projected// DOS). Normally you would now do a convolution plot using a gaussian to get a smooth DOS, but instead you can simply plot it in a scatter or vertical line plot.
+The columns correspond to the orbitals present in the basis set (hence //projected// DOS). Normally you would now do a convolution plot using a gaussian to get a smooth DOS, but instead you can also simply plot it in a scatter or vertical line plot.
+Please also note the unit of the energy, it is in $E_h$. When looking at DOS plots you may want to convert it to Electronvolt instead.
+While some of the new options to help with convergence are of numerical nature, [[howto:static_calculation#adding_smearing|the smearing is not]].
+  * Repeat the above calculation for the different multiple cells 3x3x1, 4x4x1, 5x5x1, 6x6x1 and 7x7x1
+  * Even though you are not required to do any smoothing, create the DOS plots for each simulation.
+  * Do you see why it is necessary to do the unit cell replication? Hints: does graphene have a band gap? Compare the plots for 3x3x1 and 5x5x1.
+  * .. which state ($s$, $p_x$, ..) is mainly responsible for that?
+  * Repeat the calculations for h-BN instead (use the DZVP-MOLOPT-SR-GTH basis set for boron instead of the DZVP-MOLOPT-GTH and change the lattice constant to $2.504 Å$).
+  * Create the plots again (remember: now there are two pdos files, one for each kind). What is the clear difference to graphene?
+  * Do you now understand why we need smearing?