Chemistry Notes for B.Sc. and M.Sc.

  Some Important IR Regions: ü  N ear-IR region:   4 ,000 cm –1  - 13 000 cm –1 . ü  Mid-IR region: 670-4000 cm -1 Ø  Functional group region: 1450 cm –1  - 4000 cm –1 . Ø  F ingerprint  region: 67 0 cm –1  - 1450  cm –1 . ü  F ar-IR region: 1 0 cm –1  - 67 0 cm –1     Near Infra-red (NIR) Spectroscopy: ü  The near-IR extends from approximately 13,000 cm –1  - 4000 cm –1 ü  The absorption bands in the near-infrared often are overtones and combination bands of these group frequencies (of O-H, C-H and N-H) ü  The instrumentation for NIR spectroscopy, both in transmission mode and in reflectance mode, is similar to that for UV/visible spectrometers and for mid-IR spectrometry.   Applications of NIR Spectroscopy ü  Near-infrared spectroscopy is  used in astronomy for studying the atmospheres of various  stars   by detecting the  vibrational and rotational signatu...

  Q 1: Explain the effect of conjugation, hydrogen bonding and steric factor on vibrational frequency? Q 2: Application of Far, Near and Mid-IR spectroscopy? Q 3: Application of NMR Spetcroscopy? Q 4: Applications of Mass Spectrometry or its advantages over other spectroscopic techniques? Q 5: Why Carbon NMR is less sensitive than proton NMR or disadvantages of Carbon NMR over proton NMR Q 6: Advantages of FT-NMR over CW-NMR or difference between FT-NMR and CW -NMR Q 7: Short Notes on Following: a.  McLafferty rearrangement b.  Magnetic Anisotropy (for alkenes, alkynes, aromatic compounds and aldehydes with diagrams) c.  Mechanism of spin-spin interaction or splitting of signals d.  Coupling constant and factors affecting it e.  Long range coupling f.  Simplification of complex spectra (High Field strength, Double irradiation or spin-spin decoupling, Use of Shift Reagents) g.  Nitrogen rule. h.  EI (Electron Impact Ionization) i.  CI (Ch...

  Q 1: Explain the effect of conjugation, hydrogen bonding and steric factor on vibrational frequency? Q 2: Application of Far, Near and Mid-IR spectroscopy? Q 3: Application of NMR Spetcroscopy? Q 4: Applications of Mass Spectrometry or its advantages over other spectroscopic techniques? Q 5: Why Carbon NMR is less sensitive than proton NMR or disadvantages of Carbon NMR over proton NMR Q 6: Advantages of FT-NMR over CW-NMR or difference between FT-NMR and CW -NMR Q 7: Short Notes on Following: a.  McLafferty rearrangement b.  Nitrogen rule. c.  EI (Electron Impact Ionization) d.  CI (Chemical Ionization) e.  FAB (Fast Atom Bombardment) f.  Metastable peak g.  Base Peak h.  DEPT i.  HSQC j.  HMBC k.  INADEQUATE l.  Instrumentation of Mass spectrometry m.  Proton decoupled Carbon NMR or Noise decoupled carbon NMR n.  Off-resonance proton decoupled Carbon NMR o.  Fourier Transform Carbon NMR OR Pulsed NMR...