4.3.1 Principles of Spectroscopy
Spectroscopy is used as very valuable tool to gain insights into the structural
properties of organic molecules. The method is based on a very simple physical
phenomenon, the interaction of electromagnetic radiation and matter, also known as
‘absorption’ and its counterpart ‘emission’. Since this interaction occur on molecular
or atomic dimensions, it can be explained only by quantum mechanics. For this
purpose, electromagnetic radiation can be described either as particle beam or as a
wave, the so-called wave-particle dualism. For describing the spectroscopic processes, the most important aspect is the quantization implying only discrete energy
He
Detector
CombusƟon
Carbon mode
Nitrogen mode
ReducƟon
Isotope raƟo mass
spectrometer
t ime
m/z 44
m/z 45
CO 2
N 2
Carbon mode
GC
Fig. 4.32 A principal set-up of an irm-GC/MS system for compound specific stable carbon or
stable nitrogen isotope measurements
4.3 Spectroscopy
73
Spectroscopy is used as very valuable tool to gain insights into the structural
properties of organic molecules. The method is based on a very simple physical
phenomenon, the interaction of electromagnetic radiation and matter, also known as
‘absorption’ and its counterpart ‘emission’. Since this interaction occur on molecular
or atomic dimensions, it can be explained only by quantum mechanics. For this
purpose, electromagnetic radiation can be described either as particle beam or as a
wave, the so-called wave-particle dualism. For describing the spectroscopic processes, the most important aspect is the quantization implying only discrete energy
He
Detector
CombusƟon
Carbon mode
Nitrogen mode
ReducƟon
Isotope raƟo mass
spectrometer
t ime
m/z 44
m/z 45
CO 2
N 2
Carbon mode
GC
Fig. 4.32 A principal set-up of an irm-GC/MS system for compound specific stable carbon or
stable nitrogen isotope measurements
4.3 Spectroscopy
73