ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/C2H6Se/c1-3-2/h1-2H3/file?format=sdf&get3d=True  -- InChI%3DInChI%3D1S/C2H6Se/c1-3-2/h1-2H3 could not be loaded.