Complex ¹H NMR spectra multiplets that cannot be easily understood by simple inspection are rather frequent in the daily work of the organic chemistry analyst. The multiple and excellent new techniques available from modern instruments usually provide satisfactory solutions, but there are still many cases where a simulation is necessary, at least to obtain a final confirmation. It is extremely convincing to see that a graph, obtained by calculations with chemical-shift and coupling-constant values only, can be virtually identical to the experimental spectrum. This paper describes a computer program to make such calculations. The program is free and can be downloaded from <A HREF="http://artemis.ffclrp.usp.br/NMR.htm">http://artemis.ffclrp.usp.br/NMR.htm</A> (click on SimEsp_NMR_Compil.zip). All routines are also available and may be used without any restrictions. The paper includes a fairly detailed discussion about how the calculations are made.
computer program; 1H NMR; spectrum simulation
