Iv heard alot about retributions merge with core
but thats what im here to talk about
i am wanting to know if it is possible to merge a official clan with a non official

You could always just take the people from the non official clan and put them in the official clan. So, if that is all you need to do, then it is very possible.
But if you want the clan's named changed then you would just have to do what I wrote above and ask for a name change. Very possible.

Mainly both of the leaders have to agree and the crowd too, then you would have to ask a clan admin to change the clan name for you.

Its not that hard, post it in the clans board.