is this related to an adobe program?
whoops... yes in Lightroom
You can't use Lightroom to delete "unselected" images, in the sense that you have to select photos in Lightroom to delete them. So I'm not sure what you mean. Do you mean "un-imported" images?
Why can't you move some photos to an external disk, instead of deleting them?
images are imported / edited /
now i want to archive, in the past i have exported selects as .dng or tiff and then saved to HD
but i would prefer to keep the integrity of the lightroom catalogue and not move the files
and so was curious if there was a way to delete the unselected files
Star the ones you want to keep then you can use the Filter bar to show only images that have No stars, Select all of those and go to "Photo" menu item, Remove Photo...
Or hit the backspace key then Delete from Disk button.
Or go through your images in the film strip and when an image is selected hit the x key to mark it as rejected. Then you can delete all the rejected images at one time.
There are many way to display, select and delete images from LR and your hard drive. Butr I'm not sure that is really what you are looking for.
Archiving images is not the same as removing them from the LR catalog and deleting them from your hard drive. At least not the way I think.
There's no need to create an archive the photos that is outside of Lightroom, that in my opinion is unnecessary work. There's no need to delete photos. The solution is to move the photos to a different disk, while keeping the photos in Lightroom.
Moving the photos does not affect the "integrity of the catalog" when done properly. To move the photos to a different disk, please follow the instructions in "Part 2 — Updating Folder Location" in this document: Adobe Lightroom - Find moved or missing files and folders
thanks for all the input