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Spectroscopy is the study of spectra.
Originally a spectrum was what was observed when white light was dispersed through a prism. Soon the term referred to a plot of light intensity as a function of frequency or wavelength. Planck later realized that frequency represents electromagnetic energy.
The recording and studying of spectrum of energy levels in atoms or molecules in the physical sciences is called spectroscopy. A device for recording a spectrum is a spectrometer or spectrophotometer. The latter term is used when an optical spectrum is recorded by the device.
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2 Energy of photons 3 Kinetic energy of electrons 4 Kinetic energy of ions or molecules 5 Vibrational energy 6 Analysis with spectroscopy 7 Other Topics |
A = εXb[X] + εYb[Y] + εZb[Z] + ...
A' = εXb[X] + εYb[Y]
Types of spectroscopy
There are many various branches of the study of spectra:
Energy of photons
Kinetic energy of electrons
Kinetic energy of ions or molecules
Vibrational energy
Analysis with spectroscopy
Analysis involves finding out absorbances of the analyte.Analysis of a mixture
When there is more than one absorbing species in a solution, the absorbance at a particular wavelength is the sum of absorbances from all species at that wavelength.
The composition of a mixture of two or more compounds can be found by using two or more wavelengths and by knowing ε at each wavelength for each compound. These wavelengths are usually wavelengths of maximum absorption (absorbance maxima) for the individual components. For two components, two wavelengths give two equations:
A" = εXb[X] + εYb[Y]Other Topics