ERROR opening https://cactus.nci.nih.gov/chemical/structure/InChI%3DInChI%3D1S/Mg.2NO3/c%3B2%2A2-1%283%294/q%202%3B2%2A-1/file?format=sdf&get3d=True -- InChI%3DInChI%3D1S/Mg.2NO3/c%3B2%2A2-1%283%294/q%202%3B2%2A-1 could not be loaded.