Info on 'di-1-hydroxytetrazole'?

I found this name on a number of banned shipping items lists with no further information available. Does anyone have info on this?

I'm assuming this may be 5,5'-bis(1-hydroxytetrazole) but that name also draws a blank.









[Edited on 18-8-2008 by Ritter]

This substance was made by Willand by following route:

Thanks. I was unable to locate the paper by Nicolas Willand describing this synthesis or the energetic properties of this compound. Do you have a more complete reference?

Here's my version of the precursor:





[Edited on 22-8-2008 by Ritter]