Computational Chemistry and Spectroscopy

Introduction, Scope of computational  chemistry.

Molecular mechanics / force field  methods, the force field energy, advantages and limitations of molecular mechanics methods.

Electronic Structure Methods: The Schrödinger equation, molecular Hamiltonian, Born-Oppenheimer approximation, self-consistent field theory, Koopmans’ theorem, Hartee-Fock theory, restricted and unrestricted Hartree-Fock, the variation principle, SCF techniques, Rootham-Hall equation, semi-empirical methods: CNDO, MINDO, MNDO, AM1, MNDO-PM3, limits and advantages of semi-empirical methods.

Excited slater determinants, Configuration Interaction (CI), Multi-Configuration Self-Consistent Field (MCSCF), Complete Active Space Self-Consistent Field (CASSCF), many-body perturbation theory, Møller-Plesset perturbation theory, Coupled Cluster (CC) methods, density functional theory, local density methods, gradient corrected methods, hybrid methods.

Slater and gaussian type orbitals, polarization and diffuse functions, split-valence sets, classification of basis sets, even- and well-tempered basis sets, pople style basis sets, Dunning-Huzinga basis sets, correlation consistent basis sets, extrapolation procedures, effective core potential basis sets. 

Introduction to Potential Energy Surface (PES), local minimum, global minimum, and saddle point, convergence criteria, transition structures, frequency calculations, zero-point corrections, thermo chemistry, Intrinsic Reaction Coordinate (IRC) analysis, calculation of activation and reaction enthalpies, Some illustrative examples: ethylene, 1,3-butadiene, 1-fluoropropane, vinyl alcohol,  isodesmic and isogyric reactions, natural orbital analysis.

The calculation of NMR parameters in transition metal complexes, Excitation energies of metal complexes with Time-dependent DFT, Application of Hybrid-DFT to Homogenous catalysis, DFT computation of Relative Spin  – State and Energetics of Transition Metal Compounds.

Double Resonance experiments; relaxation; multiple experiments; Nuclear Overhauser effect; Interpretation of spectra, chemical shift, shielding mechanism and anisotropic effects. Second order spectrum and analysis of AB, AMX and ABX systems. Simplification of Complicated Spectra: Aromatic induced shifts spin decoupling, spectra at higher fields. Hindered  rotation and rate products.

¹³CMR Spectroscopy:

General considerations, chemical shift, coupling constants, Nuclear Overhauser effect, Spin-spin , spin-lattice relaxations. Off resonance decoupling,  DEPT Interpretation of 1H and 13CNMR spectra. Introduction to 2DNMR: Techiques like COSY, HSQC, NOESY and ROSEY etc.

Introduction, ion production, EI and CI, techniques fragmentation, factors influencing ion abundance, single and multiple bond cleavage, doubly charged ions rearrangements, cleavage associated with common functional groups. Mc Lafferty rearrangement, molecular ion peak, metastable ion peak, Nitrogen rule and    interpretation of mass spectra, HRMS Structure elucidation based on spectroscopic  data.