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--- exercises:2016_summer_school:geometry_and_cell_optimization [2016/08/22 21:18] – ibethune
+++ exercises:2016_summer_school:geometry_and_cell_optimization [2020/08/21 10:15] (current) – external edit 127.0.0.1
@@ Line 91: / Line 91: @@
 &END MOTION
+</code>
+You will also need to initial geometry file ''NaCl.pdb'':
+<code>
+REMARK   4 NaCl COMPLIES WITH FORMAT V. 2.0
+CRYST1    5.620    5.620    5.620  90.00  90.00  90.00 P 1
+HETATM    1 Na   NMO     0       0.000   0.000   0.000  1.00  0.00      NMO Na
+HETATM    2 Cl   CMO     0       2.810   2.810   2.810  1.00  0.00      CMO Cl
+HETATM    3 Na   NMO     0       0.000   2.810   2.810  1.00  0.00      NMO Na
+HETATM    4 Cl   CMO     0       2.810   0.000   0.000  1.00  0.00      CMO Cl
+HETATM    5 Na   NMO     0       2.810   0.000   2.810  1.00  0.00      NMO Na
+HETATM    6 Cl   CMO     0       0.000   2.810   0.000  1.00  0.00      CMO Cl
+HETATM    7 Na   NMO     0       2.810   2.810   0.000  1.00  0.00      NMO Na
+HETATM    8 Cl   CMO     0       0.000   0.000   2.810  1.00  0.00      CMO Cl
+TER       9      UNK     0
+END
 </code>
@@ Line 216: / Line 232: @@
 Copy the input template to a new file and change the ''RUN_TYPE'' to ''CELL_OPT''. You'll also need to ask the code to calculate the stress tensor (in ''FORCE_EVAL'' section) ''ANALYTICAL''ly! Also define the ''CUTOFF'' and ''SCALING_FACTOR''. Start the cell optimization from small cells (''SCALING_FACTOR 0.85'') or large cells (''SCALING_FACTOR 1.10'') - do you get the same results?
-If you have access a machine with several cores (16 or so ideally) check whether increasing the supercell size (''NREP'' variable) affects the results.
+If you are running on ARCHER, use some larger parallel jobs to check whether increasing the supercell size (''NREP'' variable) affects the results.