How to Defrag RAID Group - Flare 28

I have been searching most of the day through Powerlink and various blogs and EMC documents, but haven't been able to find an answer to this. All I need to do is defrag one particular RAID group because the largest contiguous space is not large enough. If I right-click on the RAID Group, I do not have an option to defrag. The only option I have is within properties to change the defragmentation speed. I have found countless forum posts and docs that reference defragmentation, but none of them seem to explain exactly how you can do it manually. Can someone please give the specific steps or point to a document that outlines them? I appreciate it.