To add or modify a localized charge, you can activate one of the following tools:
The tools can be used to increment or decrement the local charge of an atom by clicking on the atom while the appropriate tool is active. Local charges can also be added to atoms located in fragments with the following restrictions: only one atom in a fragment can bear a local charge; if the fragment has a bond, only the bonded atom can bear the charge; and if charges are already present in the fragment, no other local charge can be supported by the fragment. In fragments, local charges are limited to -1 and +1 in this version of GChemPaint.
To display the charge at a position different from the default one, drag the charge to the wanted position while pressing the mouse button. Pressing the Shift key and/or the Control key change the behavior while dragging.