Update index.md

Author: ejmeitz

docs/src/index.md

@@ -12,7 +12,7 @@
 #### Monoatomic Bravais Lattices:
 Whenever possible crystals are implemented using a conventional unit cell so that patterning a simulation cell is simple. A trinclinic boundary will work for the remaining lattices.
 
- SimpleCrystals.jl re-exports [Unitful.jl](https://painterqubits.github.io/Unitful.jl/stable/) and [StatcArrays.jl](https://github.com/JuliaArrays/StaticArrays.jl) and can handle any atomic symbols from [PeriodicTable.jl](https://github.com/JuliaPhysics/PeriodicTable.jl). For example, The code below creates an FCC crystal of carbon with a conventional cell that is 5.4 Angstroms. The cell is patterened 4 times in the x, y, and z directions. The coordinates can be obtained in code with the `atoms` member variable or saved to a XYZ file with `to_xyz()`.
+ SimpleCrystals.jl re-exports [Unitful.jl](https://painterqubits.github.io/Unitful.jl/stable/) and [StatcArrays.jl](https://github.com/JuliaArrays/StaticArrays.jl) and can handle any atomic symbols from [PeriodicTable.jl](https://github.com/JuliaPhysics/PeriodicTable.jl). For example, the code below creates an FCC crystal of carbon with a conventional cell that is 5.4 Angstroms. The cell is patterened 4 times in the x, y, and z directions. The coordinates can be obtained in code with the `atoms` member variable or saved to a XYZ file with `to_xyz()`.
 
 ```julia
 a = 5.4u"Å"
@@ -24,7 +24,7 @@ to_xyz(fcc_crystal, raw"./positions_fcc.xyz")
 #### 3D Bravais Lattices
 All 3D Bravais lattices created from the SimpleCrystal's API and visualized in [OVITO](https://ovito.org/). The radius of the atoms is chosen arbitrarily in OVITO.
 
-
+```@raw html
 <table>
     <tr>
         <th>Crystal Family</th>
@@ -84,7 +84,7 @@ All 3D Bravais lattices created from the SimpleCrystal's API and visualized in [
     </tr>
 
 </table>
-
+```
 
 #### Other 3D Structrues
 Diamond and HCP are also implemented as part of the API: 
@@ -206,10 +206,14 @@ fcc_crystal = FCC(a, :C, SVector(4,4,4))
 to_xyz(fcc_crystal, raw"C:\Users\ejmei\Desktop\positions_fcc.xyz")
 ```
 
-To get the list of atoms in code you can use the `atoms` member variable. The code below will return the array of atoms that the to_xyz() function builds internally.
+To get the list of atoms in code you can use the `atoms` member variable. The code below will return the array of atoms that the to_xyz() function builds internally. AlLternatively, you can loop over the crystal object which will iterate through the `crystal.atoms` list.
 
 ```julia
 a = 5.4u"Å"
-fcc_crystal = FCC(a, :C, SVector(4,4,4))
+fcc_crystal = FCC(a, :C, SVector(2,2,2))
 atoms = fcc_crystal.atoms
+
+for atom in fcc_crystal
+    #do something
+end
 ```