principle of FTIR

Answer Posted / pratima bhandarkar

The principle of FTIR is based on the fact that bonds and
groups of bonds vibrate at characteristic frequencies. A
molecule that is exposed to infrared rays absorbs infrared
energy at frequencies which are characteristic to that
molecule. In a molecule, the differences of charges in the
electric fields of its atoms produce the dipole moment of
the molecule. Molecules with a dipole moment allow infrared
photons to interact with the molecule causing excitation to
higher vibrational states. Diatomic molecules do not have a
dipole moment since the electric fields of their atoms are
equal. During FTIR analysis, a spot on the specimen is
subjected to a modulated IR beam. The specimen's
transmittance and reflectance of the infrared rays at
different frequencies is translated into an IR absorption
plot consisting of reverse peaks. The resulting FTIR
spectral pattern is then analyzed and matched with known
signatures of identified materials in the FTIR library.

Is This Answer Correct ?    22 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

As per ICH related substances stability trend limit from initial to shelf life

2678


How will u perform degradation study in detectors other thann PDA in HPLC Methodology

2024


In HPLC Calibration, On which basis RSD Limit of noise test is fixed (NMT 33.0 % )

2966


cefoperozone and sulbactam inj. hplc test method

2134


Why only hydroxy naphthol blue indicator is used for standardisation of 0.05M EDTA solution instead of solochrome Black T or Euriochrome Black T indicator which is used for all sample analysis with 0.05M EDTA solution?

2220






AT WHAT CONDITIONS WILL YOU ANALYSE A SAMPLE,WHICH ARE PRESERVED AT OTHER THAN THE AMBIENT CONDITIONS?(ie COLD STORAGE SAMPLES BELOW 20* CENTIGRADE?

1611


why digestion require in icpms?

309


Why use only methanol,used determinationof moisture content not use other solvents

888


mahagenco syllabus for the post of chemist

5746


Hi sir if any product monograph not given known impurities (may be 5 impurities) specifications then how we require to proceed for inhouse formulation?

288


effect of pore size, pore volume, partical size, column length, carbon load on retention time? what is carbon load? what is the use?

334


if you have given one product then how you determine the impurity in that?

296


USP methodology, EP methodology, IP methodology, among three if possible to use one methodology for qualify working standard to use USP, EP, IP ? Please explain...

1564


What is delay volume?

861


for inorganic molecules require to do RS, Assay and disso?

257