Hi Mandar, > On Dec 13, 2023, at 03:39, Mandar Kulkarni <mandar.kulkarni.c...@gmail.com> > wrote: > I could not figure out how Rdkit is guessing it as 2D structure, as there is > no such information in SDF.
Line 2 of the SDF record looks something like: RDKit 2D This line has the format (quoting from the documentation): IIPPPPPPPPMMDDYYHHmmddSSssssssssssEEEEEEEEEEEERRRRRR A2<--A8--><---A10-->A2I2<--F10.5-><---F12.5--><-I6-> ) where "User's first and last initials (l), program name (P), date/time (M/D/Y,H:m), dimensional codes (d) such as 2D or 3D, scaling factors (S, s), energy (E) if modeling program input, internal registry number (R)" In the example I gave, most of these fields are blank, except for the program name ("RDKit") and the dimension code "2D" in columns 21-22 (if I counted right). The dimension code indicates the structure is expected to be in 2D. > Is there any more information need to provide SDMolSupplier to make it > understand it's a 3D molecule? It is only a warning. RDKit interprets the molecule as 3D despite the warning. The file format documentation also says: "The “dimensional code” is maintained explicitly. Thus “3D” really means 3D, although “2D” will be interpreted as 3D if any non-zero Z-coordinates are found. Best regards, Andrew da...@dalkescientific.com _______________________________________________ Rdkit-discuss mailing list Rdkit-discuss@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/rdkit-discuss