Studies of the X-ray absorption spectra of some methylcyano esters

Density functional theory (DFT) has been applied to simulate core-excited photoabsorption spectra for some methylcyano esters within a transition potential (TP) framework. Our calculations for methylcyano formate at the N and O K-edges are consistent with previous experimental spectra. For methylcyano acetate the photoabsorption spectra at the N and O K-edges were reinvestigated experimentally. Contrary to the previous experiment, only one main peak was observed at the N K-edge and this peak was assigned to N(1s) →π∗ excitation. This result was supported by our theoretical calculations. The general trends in the X-ray absorption spectra and the site-specific bond scission of methylcyano esters at the N and O K-edges are also discussed.