"Cu", "CuKa1", "CuKa1Ka2" CuKa1 : 1.54056 CuKa1Ka2 : =(1.54056*2 + 1.544398)/3 = 1.54184 Cu : 1.542 _Originally posted by @sbillinge in https://github.com/diffpy/diffpy.labpdfproc/pull/151#discussion_r1915705212_