For many years I used to add a text box containing a single bond to a double bond which always looks messy and goes awry when the text box goes walkies. My colleague Dean Raul showed me a better way. Now I type NZZ and it Autocorrects using the method described here to a nice triple bond which looks like this:

See here for how to find the Unicode symbol for the triple bond on the keyboard.
To find the Unicode symbol of any character use my macro here.