University:
Swansea University
Course:
PM134 | Microbiology
Academic year:

2023
Views:

463

Pages:

3
Author:

Sanjeev K

SPECTROSCOPY Intraction b/w Matter and lighteg of spectrossopyElectromagnetic radiation - EMR Ps a sey propagating wave in spacewith electric and magnetic components of wave like natureEMR exhibits both wave. and particle properties at the sametime.EMR are classified either by wavelength I by frequency of the waveWavelengththeyouDirectionSrEGammaRadio Misuwave Infared Visible UV X-ray10310-2 (10-5) (5x106) (10-8) (10-10)Rays(10-12)Frequency and Wavelength ave. inversely PropotionalofSpectroropyInteractionb/wmatterandEMR.Use of absorption emission (scattering of EM by matter toqualitatively / quantitatively study the matter.The matter can be atome molecules atomic / molecular ions/solidInteraction of EM radiation with matter can cause redirectionof the radiation and/or transition b/w the energy levels of the molecules. atomy S2S,AbsorbedEmilled fluoracienceoviledlightIII1light.y.S.7SoGround stateov,Absorption - A transition from a lower level to a higher levelwith transfer of energy from the radiation field to an absorberatom, molecule / solid.Emission - A transition from a higher level to a lower levelwith transfer of energy from the emitter to the radiationfield.If no radiation emitted , the transition from higher to lowerenergy levels is called non-radiative dray.Scattering - Redirection of light due to its interaction withmatter. Scattering might | might not occur with transfer ofenergy ie ,different wavelength might not be observed.electromograticTypes of EM Spectroscopy1)Absorption SpectroscopyMatter can capture EM radiatin and convert the energy ofa photon to Internal energy is called absorption. Energy change of the absorber can be said as transition /an excitation from a lower energy to a higher energy levelThe study of Electromagnetic radiation spectra ab sorbed byatome / molecules that change energy levels.1)Emission Spectroscopystudy of electromagnetk radiation spectra given lower off byatoms /molecules that undergo a transition to a energyIRlevel.madiowaThis wndn is called fluoresence / phos phoresienceIt deals with visible light and shorter wavelengths,since fluorescence is less likely to happen with longwardengths.TLight Source can beWEIR1UV (=age E6-C=conjugationatAsee-soorm200mm2Visible400us3Infrared. (tunctionalfaruvarp)Electrons are Promoted to higher orbital by UY Orvisible light / , vibrations are excited by IR light androtation are excited by microwavesStreeting frequencyIR is the most common, ,as practically all substanceabsorb IR very selectively, UV and visible light are usedfor simple pieces of evidence like drugs.