the act of decomposing a substance into its constituent elements

of or relating to or involving spectrometry

of or relating to or involving spectrometry

the use of spectroscopy to determine the masses of small electrically charged particles

the use of spectroscopy to study atomic or molecular resonances in the microwave spectrum

The branch of spectroscopy concerned with the measurement of the intervals between atomic or molecular energy levels that are separated by frequencies from about 105 to 109 hertz, as compared to the frequencies that separate optical energy levels of about 6 × 1014 hertz.