COMPARED C-13 NMR-SPECTRA OF ACETANILIDE AND N-METHYLACETAMIDE

Acetanilide and N-methylacetamide are both crystals in which the exist ence of non linear excitations (self-trapped excitons or acoustic pola rons) have been postulated as an explanation of the unconventional ami de spectroscopy. This theory is debated and a dynamic proton transfer along the hydrogen bond could be an alternative explanation for the un expected sidebands and temperature dependences. Our compared C-13 NMR study demonstrates a similar behaviour for the EFG at the N-14 atom in these both compounds, indicating a very close electronic density arou nd the nitrogen in both cases, and thus does not confirm the hypothesi s of a proton transfer in N-methylacetamide.