Reactions and retrosynthesis from 1985 to today
How reactions are written down and searched backwards, from RXN files, reaction SMILES and SMIRKS to the USPTO and ORD datasets and open retrosynthesis tools.
How chemistry software works
Short explainers on the notations, file formats and methods behind the tools on this site.
All posts
Spectroscopy file formats from 1988 to today
How NMR, IR, UV-Vis and mass spectra are stored on disk, from JCAMP-DX to mzML, nmrML and NMReDATA, and which formats keep the structure with the spectrum.
Cheminformatics file formats from 1971 to today
How molecules are stored on disk, from the PDB format and MDL molfiles to CIF, CML, CDXML and CXSMILES, with ethanol as the running example.
Chemistry line notations from 1949 to today
How chemists write a molecule as one line of text, from WLN and SMILES to InChI and the notations made for machine learning, with caffeine as the running example.