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--- exercises:2015_ethz_mmm:basis_sets [2015/04/16 14:17] – oschuett
+++ exercises:2015_ethz_mmm:basis_sets [2015/04/16 14:27] – oschuett
@@ Line 1: / Line 1: @@
 ====== Basis Sets ======
-In this exercise you will compare different basis sets and use them for computing the binding energy of an H2 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]].
-===== Part I: Different basis sets for H and H2 =====
+===== Part I: Different basis sets for H and H$_2$ =====
 ==== 1.Step ====
@@ Line 89: / Line 89: @@
 ==== 3.Step ====
-Repeat the procedure for H2. 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 H2 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 H2 =====
+===== Part II: Estimate the binding energy of H$_2$ =====
-Binding energy: \\
+Based on the formula for the //binding energy//, you can now update your table.
 \[ \sum E_\text{products} -  \sum E_\text{reactants} = E(H_2) - 2 \cdot E(H) \]
-<note important> The binding energy value is significant only if the same basis is used for both reactants and products. </note>
+^ Basis set                  ^ Energy H [$E_h$] ^ Energy H$_2$ [$E_h$] ^ Distance H$_2$ [$Å$] ^ Binding Energy H$_2$ [$E_h$] ^
-You can now update your table:
-^ Basis set                  ^ Energy H [$E_h$] ^ Energy H2 [$E_h$] ^ Distance H2 [Å] ^ Binding Energy H2 [$E_h$] ^
 | mybasis (from given input) | ....             | ....              | ....            | ....                      |
 | basis try 1                | ....             | ....              | ....            | ....                      |
@@ Line 113: / Line 109: @@
 | pc-2                       | ....             | ....              | ....            | ....                      |
 | ....                       | ....             | ....              | ....            | ....                      |
-===== Part III: Questions =====
-- What is the effect of:\\
+<note important>The binding energy is only significant if all terms were calculated with the same basis-set.</note>
-  * increasing/decreasing the value of the exponents for the given basis?
-  * adding sets with p,d symmetry to the basis? You have the same effect in H and H2?
+===== Part III: Questions =====
-===== Part IV: Additional basis sets =====
+  - What is the effect of changing the exponents in a basis-set?
+  - What is the effect of adding p- and d-function to the basis-set? Do H and H$_2$ respond differently?
+===== Appendix: Literature Basis-Sets =====
+<code>
 H  pc-0
@@ Line 161: / Line 157: @@
 .25000000          1.00000000
+</code>