KEY POINTS

• CLASSIFICATION OF SPECTROSCOPY

  1. Electromagnetic
  2. Electron
  3. Mass
• CLASSIFICATION OF ELECTROMAGNETIC SPECTROSCOPY

  1. Emission
  2. Absorption
  3. Scattering
• ABSORPTION SPECTROSCOPY

  1. Vibrational
  2. Atomic
  3. UV/Visible
  4. Mossbauer
• 2 CLASSIFICATIONS OF ABSORPTION SPECTROSCOPY

  1. Atomic Absorption
  2. Infrared
• One of the most useful applications of light scattering spectroscopy is Raman spectroscopy
• Infrared spectroscopy is widely used in both research and industry as a simple and reliable technique for measurement, quality control and dynamic measurement.
• Infrared spectroscopy


  It is perhaps the most widely used method of applied spectroscopy
• Infrared Spectroscopy


  It is of special use in forensic analysis in both criminal and civil cases, enabling identification of polymer degradation for example.
• The scattering process is much faster than the absorption/emission process.
• THREE MODULES IN MASS SPECTROSCOPY

  1. Ion source
  2. Mass Analyzer
  3. Detector
• Mass spectroscopy is now in very common use in analytical laboratories that study physical, chemical, or biological properties of a great variety of compounds.
• OTHER TYPES OF SPECTROSCOPY

  1. Acoustic
  2. Dialectric
  3. Mechanical
• Beer-Lambert Law is an empirical relationship that relates the absorption of light to the properties of the material through which the light is travelling.
• Emission Spectroscopy


  is the study of electromagnetic radiation spectra given off by atoms or molecules that undergo a transition to a lower energy level
• Emission spectroscopy has such a process is called fluorescence or, under certain conditions, phosphorescence.
• Generally, emission spectroscopy deals with visible light and shorter wavelengths, since fluorescence is less likely to happen with long wavelengths.
• Absorption Spectroscopy


  is the study of electromagnetic radiation spectra absorbed by atoms or molecules that change energy levels; the atoms usually positioned between a radiation source and the observer.
• Absorption spectroscopy is often used as an analytical technique; specific chemical compounds have a specific absorption spectrum that acts as a fingerprint.
• Absorption spectroscopy can be used to determine the concentration of chemical compounds in samples
• ABSORPTION SPECTROSCOPY

  • Vibrational spectroscopy - absorption of infrared radiation,
  • Atomic absorption - is a technique for determining the concentration of a particular metal element in a sample
  • UV/visible spectroscopy - absorption of ultraviolet and visible light
  • Mossbauer spectroscopy - Measures the absorption of gamma rays by atoms bound in a solid as a function of gamma-ray energy. This is not an analytical technique; it is a means to understand certain microscopic processes in matter.
• ion source, which splits the sample molecules into ions
• mass analyzer, which sorts the ions by their masses by applying electromagnetic fields
• detector, which measures the value of an indicator quantity and thus provides data for calculating the abundances of each ion present