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exercises:2018_ethz_mmm:lennard_jones_cluster_2018

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exercises:2018_ethz_mmm:lennard_jones_cluster_2018 [2018/02/23 08:37] dpasseroneexercises:2018_ethz_mmm:lennard_jones_cluster_2018 [2018/02/23 08:48] dpasserone
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 <note important>NOTE ON THE UNITS: CP2K USES SO CALLED "atomic units". Meaning that the resulting energies are expressed in Hartree,  <note important>NOTE ON THE UNITS: CP2K USES SO CALLED "atomic units". Meaning that the resulting energies are expressed in Hartree, 
 **1 Hartree=27.2114 eV**.  **1 Hartree=27.2114 eV**. 
-In the input file, the epsilon value (depth of the well) is expressed in KT units, namely, in "temperature" units (there is a Boltzmann constant to make units work...). **The sigma value is in Angstrom.**+In the input file, the epsilon value (depth of the well) is expressed in KT units, namely, in "temperature" units (there is a Boltzmann constant K_b to make units work...). <code>1 Kelvin*K_b=3.2E-6 Hartree</code>. Using this conversion factor you can transform the epsilon value into Hartree, and the total energy can be expressed in units of epsilon.  **The sigma value is in Angstrom.**
 </note> </note>
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 <note tip>Assignment:  <note tip>Assignment: 
   - Report the energy of the minima, compare it with the ones of the initial configurations.    - Report the energy of the minima, compare it with the ones of the initial configurations. 
 +  - After converting the energy into "epsilon" units, estimate the number of bonds in the cluster, assuming a pairwise interaction.
   - Plot q4 vs. energy and q4 vs. optimization steps, for the two cases. Discuss the results. Are the minima in two separate basins?   - Plot q4 vs. energy and q4 vs. optimization steps, for the two cases. Discuss the results. Are the minima in two separate basins?
   - Report the value of the order parameter of the minumum, and discuss what you see   - Report the value of the order parameter of the minumum, and discuss what you see
exercises/2018_ethz_mmm/lennard_jones_cluster_2018.txt · Last modified: 2020/08/21 10:15 by 127.0.0.1