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--- exercises:2015_ethz_mmm:basis_sets [2015/04/16 14:20] – oschuett
+++ exercises:2015_ethz_mmm:basis_sets [2020/08/21 10:15] (current) – external edit 127.0.0.1
@@ 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 $H_2$ 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]].
-===== Part I: Different basis sets for $H$ and $H_2$ =====
+===== Part I: Different basis sets for H and H$_2$ =====
 ==== 1.Step ====
@@ Line 89: / Line 89: @@
 ==== 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. Howto run a geometry optimization was covered in a [[geometry_optimization|previous exercise]]. Note that the equilibrium distance will 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.
@@ Line 100: / Line 100: @@
-^ 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) | ....             | ....              | ....            | ....                      |
 | basis try 1                | ....             | ....              | ....            | ....                      |
@@ Line 110: / Line 110: @@
 | ....                       | ....             | ....              | ....            | ....                      |
-<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 =====
+  - 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 set? Do H and H$_2$ respond differently?
-  * 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 $H_2$?
-===== Part IV: Additional basis sets =====
+===== Appendix: Literature Basis Sets =====
+<code>
 H  pc-0
@@ Line 160: / Line 157: @@
 .25000000          1.00000000
+</code>