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exercises:2015_ethz_mmm:basis_sets [2015/04/16 14:20] oschuettexercises:2015_ethz_mmm:basis_sets [2015/04/16 14:28] oschuett
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 ====== Basis Sets ====== ====== Basis Sets ======
-In this exercise you will compare different basis sets and use them for computing the binding energy of an $H_2$ molecule.+In this exercise you will compare different basis sets and use them for computing the binding energy of an H$_2$ molecule.
  
 The cp2k basis set format is described in detail [[:basis_sets|here]]. The cp2k basis set format is described in detail [[:basis_sets|here]].
  
-===== Part I: Different basis sets for $Hand $H_2$ =====+===== Part I: Different basis sets for H and H$_2$ =====
 ==== 1.Step ==== ==== 1.Step ====
  
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 ==== 3.Step ==== ==== 3.Step ====
-Repeat the procedure for $H_2$. For this you will have to add a second H atom to the coordinate section and run a geometry optimization to determine the equilibrium distance. Note that this equilibrium distance might also depend on your basis-set.+Repeat the procedure for H$_2$. For this you will have to add a second H atom to the coordinate section and run a geometry optimization to determine the equilibrium distance. Note that this equilibrium distance might also depend on your basis set.
  
-<note important> The $H_2$ molecule does not have unpaired electrons. Remember to take out the LSD and MULTIPLICITY keywords.</note>+<note important> The H$_2$ molecule does not have unpaired electrons. Remember to take out the LSD and MULTIPLICITY keywords.</note>
  
-===== Part II: Estimate the binding energy of $H_2$ =====+===== Part II: Estimate the binding energy of H$_2$ =====
  
 Based on the formula for the //binding energy//, you can now update your table. Based on the formula for the //binding energy//, you can now update your table.
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-^ Basis set                  ^ Energy $H[$E_h$] ^ Energy $H_2$ [$E_h$] ^ Distance $H_2$ [$Å$] ^ Binding Energy $H_2$ [$E_h$] ^+^ Basis set                  ^ Energy H [$E_h$] ^ Energy H$_2$ [$E_h$] ^ Distance H$_2$ [$Å$] ^ Binding Energy H$_2$ [$E_h$] ^
 | mybasis (from given input) | ....             | ....              | ....            | ....                      | | mybasis (from given input) | ....             | ....              | ....            | ....                      |
 | basis try 1                | ....             | ....              | ....            | ....                      | | basis try 1                | ....             | ....              | ....            | ....                      |
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 | ....                       | ....             | ....              | ....            | ....                      | | ....                       | ....             | ....              | ....            | ....                      |
  
-<note important>The binding energy is only significant if all terms were calculated with the same setting, including the basis-set.</note>+<note important>The binding energy is only significant if all terms were calculated with the same basis-set.</note>
  
 ===== Part III: Questions ===== ===== Part III: Questions =====
- +  - What is the effect of changing the exponents in a basis set
-- What is the effect of:\\ +  - What is the effect of adding p- and d-function to the basis setDo H and H$_2respond differently?
-  * increasing/decreasing the value of the exponents for the given basis? +
-  adding sets with p,symmetry to the basis? You have the same effect in $Hand $H_2$? +
- +
- +
-===== Part IV: Additional basis sets =====+
  
  
 +===== Appendix: Literature Basis Sets =====
  
 +<code>
 H  pc-0 H  pc-0
   2   2
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           1.25000000          1.00000000           1.25000000          1.00000000
  
- +</code>
  
  
exercises/2015_ethz_mmm/basis_sets.txt · Last modified: 2020/08/21 10:15 by 127.0.0.1