Using one part of a disk in a raid 5 volume, and the other part as a single volume

hi, forgive me if this has been answered, i poked around but didn't see anything.

so let's say i have 5 disks total. 4 of the disks are all the same size (6tb each), but the 5th one is larger (8tb).

i understand that i can set up a raid-5 volume using ALL of the disks, including the largest one, with the understanding that only 6tb of that large disk would be used in that raid-5 volume.

this however, means that on that 8tb disk, there's 2tb not being used in that raid-5 volume. can i define that extra 2tb as a single, separate volume and use it?

thanks!