This paper continues computer analysis of the un-indexed diffraction patterns in the ICDD PDF-2 database. Diffraction data of 178 different Ta compositions were selected from the database volumes №№1-50.
Experimental and calculated interplanar spacing and differences (dD = Dexp - Dcal) are listed in tables, which are presented in this paper. Number of reflections in a database cards was reduced to 12, which is sufficient to identify the crystalline phase. Exceptions were in the case of less number of reflections. Selected crystal lattices, in a few exceptions (low elevation), meet the necessary condition abs (dD) < (last sign Dexp), and also the modern authenticity criteria.
