## Chapter 4. Advanced actions

In this chapter you'll find more advanced action to edit your document.

### The library

molsKetch has a library with frequently used structures and functional groups. Use can also add structures and groups yourself.

#### Adding a molecule from the library

To add a molecule from the library, select the correct tab on the left side of the window. Next, select the desired molecule and double-click on it to add it to the scene. After that, you can move and edit the molecule just like any other structures in the document.

#### Adding a molecule to the custom library

To add a molecule to the custom library, first switch to move mode and select the desired molecule. Next, select the correct tab on the left side of the window and click on "Add...". Enter a name in the appearing dialog and press OK to add the molecule.

#### Delete a molecule from the custom library

To delete a molecule from the custom library, select the item to delete. Next, click on "Delete" to delete the item. This action cannot be undone.

### The clipboard

In molsKetch, you can use the clipboard to cut, copy or paste molecules in the current document. Also, the selection will be put on the system clipboard as image for use in other programs. To use cut and copy, first select molecules from the move mode. Use control to select more than one molecule at a time. Paste will only be available if molecules are present on the internal clipboard.

### Editing preferences

Several preferences can be changed to change the way molsKetch draws structures.

#### Automatics add hydrogens

When this option is set, molsKetch will automatically add hydrogens to make the atom neutral. This will only effect the lightest elements.

#### Show neutral carbon atoms

When this option is unset, molsKetch will hide neutral carbon atoms. This results in a bond-only appearance.

#### Show neutral hydrogen atoms

When this option is unset, molsKetch will hide neutral hydrogens in structures.

#### Show atom charge

When this option is set, molsKetch will draw a charge indication if a atom isn't neutral.

#### Bond length

Here you can enter the bond length used in the dynamic grid. It's the distance between the click and the grid points. This setting doesn't effect existing bonds.

#### Bond angle

Here you can enter the number of points used in the dynamic grid, essentially determining the bond angle used in hinting. You can use this setting to draw cyclostructures with a specific number of atoms.

### The information box

The information box shows information about the current item. Here you'll find things like the molecule formula, the molecular weight and the total charge. You can use the context menu to copy this information to other programs.