The /i isotopic layerStep 16 of 17 of the InChI walkthrough. The isotopic layer is the most mechanical of them all: name the labelled atoms by canonical number and give the shift from the rounded average mass. Labelled hydrogens are written D and T instead. Methanol labelled on the methyl gives /i1D3 — three deuteriums on atom 1.It opens on [2H]C([2H])([2H])O, drawn live, so the layer under discussion changes as you change the structure.Convert a structure to its InChI and InChIKey and back, convert a whole CSV, XLSX or SDF file, learn how the identifier is derived, and practise writing its layers. The InChI engine is WebAssembly running in your browser, so the tool needs JavaScript — and nothing you open ever leaves your machine.

Convert — a structure in, an InChI out

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Tutorial — how an InChI is derived

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Cheatsheet — every layer in a table

Tests — the IUPAC regression corpora

Download — take the engine away

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