Help removing a corrupt Iphoto library

Hi All

I am posting this here as i don't think its a iPhoto specific issue, rather a corrupt file issue

I was hoping some one can provide wisdom in removing a corrupt iPhoto Library

The file suggests it is 500Gig in size, and no matter what i try i can't delete it

What i have tried

Deleting it through the trash can - system just hangs

Deleting using OmniDiskSweeper, using this app it suggests the file size is 11Gig, but when you ask it to trash it again just hangs

Running disk verify and repair to see if that would resolve the problem

Repair the file by holding down Command and Option while opening in iPhoto - it brought up an error message and would not let me proceed

I have even tried deleting using Terminal with no success, however in saying that i am a beginner using this launguage

At the moment my Mac thinks its occupying 50% of my hard drive space, i know it not that size, but i am at my wits end

I would be grateful if any one could help me solve this problem

Note i am running the latest software, and i no longer require this file