CID spectra of protonated molecules for seven methyl esters

These mass spectra were obtained at a collision energy of 10 eV; all the spectra other than those of methyl acetate (a) were acquired by a Q Exactive Focus quadrupole-orbitrap mass spectrometer (Thermo Fisher Scientific), whereas acetic acid spectra were obtained by a TSQ Quantum triple-quadrupole mass spectrometer (Thermo Fisher Scientific). Analyte ionization was performed using an atmospheric pressure corona discharge ionization technique.