Spectroscopy-I

Some important aspects of IR and Raman spectra: Classificatin of normal modes of molecular vibrations and IR and Raman active modes in some simple molecules. CHaracteristic group vibrations.

Electronic and coupling effect on group  vibration frequency. Application of IR and Raman spectra: determination of structure of some simple molecules(CO₂, SO₂, N₂O), determination of structure of H₂O and NH₃ through the normal modes of analysis, effect of coordination of ligands on vibrational spectra, determination of geometrical isomers of coordination compounds, identification of linkage isomers.

Nuclear Quadrupole Resonance Spectroscopy: Introduction, basic principles of NQR spectroscopy, NQR transition energies for the axially and non-axially symmetric systems, effect of a magnetic field (Zeeman effect) on NQR transitions, conditions to observe the NQR signals(in brief). Applications: interpretation of eQq data, effect of crystal lattice on the magnitude of eQq, structural information from NQR spectra.

Coupling scheme (orbit-orbit, spin-spin and spin orbit coupling,  determination of ground state, spectroscopic ground states, selection rules for electronic transitions, splitting of dⁿ terms in octahedral and tetrahedral field. Correlation diagrams, Orgel and Tanabe-Sugano diagrams (d¹-d⁹ states), spin cross-over; field strength, nephelauxetic series, calculations of Racah parameters (B and C). Applications of Tanabe-Sugano diagrams in determining D_o from spectra. Charge transfer spectra and its application in inorganic & coordination compounds.

Basic principle, ionization process, Koopmen’s theorem, photoelectron spectra of simple molecules, ESCA and its applications, Auger electron spectroscopy (basic idea), spectra of transition metal complexes, charge transfer spectra.

Some basic elements of ESR spectroscopy, relaxation processes: spin-lattice relaxation, spin-spin relaxation and exchange interaction. Zero field splitting and Kramer’s      degeneracy, ‘g’ value and factors affecting ESR lines, Hyperfine interaction: isotropic and anisotropic hyperfine interaction, spin Hamiltonian, spin densities and McConnell relationship, measurement techniques,  application to transition metal complexes (having one unpaired electron) including biological systems.

Principles of Mossbauer(MB) spectroscopy, Isomeric shift in MB spectroscopy, Quadrapole interaction and splitting of the MB spectral lines, effect of a magnetic field on the MB spectrum, magnetic hyperfine interaction, application of technique to the studies of bonding and structure determination of Fe⁺², Fe⁺³, Sn⁺² and Sn⁺⁴ compounds.