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--- exercise:monte_carlo_ice [2014/05/23 14:00] – oschuett
+++ exercise:monte_carlo_ice [2014/05/23 15:46] – oschuett
@@ Line 1: / Line 1: @@
 ====== Properties of Ice from Monte Carlo Simulations ======
+<note important>
+  - Add the line ''PRINT_COORDS .FALSE.'' in the ''TMC'' section. It disables the output of the coordinate trajectory and thus avoids the files-size problem.
+  - Add the line ''RND_DETERMINISTIC 42'' to the ''TMC'' section to choose a random number seed. You have to replace ''42'' with different values to obtain different samplings.
+</note>
 In this exercise we will use Monte Carlo sampling to calculate the [[wp>Relative_permittivity|dielectric constant]] and the [[wp>Thermal_expansion#Coefficient_of_thermal_expansion| thermal expansion coefficient]] of the disordered hexagonal phase (Ih) of water ice. In order to speed up the calculation we are going to use the simple SPC/E water model. For more information see: [[doi>10.1063/1.1568337]]. A DFT-version of the calculation can be found here: [[doi>10.1021/jp4103355]].
@@ Line 102: / Line 107: @@
   RUN_TYPE TMC
   PRINT_LEVEL LOW
-  WALLTIME 2:00:00
+  WALLTIME 1:00:00
 &END GLOBAL
 &MOTION
   &TMC
+      RND_DETERMINISTIC 42 !<=== Change this number to obtain different samplings
+      PRINT_COORDS .FALSE. !this avoids the 'file size exceeded' problem
       GROUP_CC_SIZE 0
       NUM_MC_ELEM 100000