Learning objectives
The aim of the course is to give the participants a thorough knowledge of the basic and advanced tools for the structural analysis or organic compounds through monodimensional and bidimensional NMR spectroscopy.
Prerequisites
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Course unit content
Magnetic properties of nuclei: angular momentum and spin angular momentum. NMR Frequencies and Chemical shift. Energy levels and NMR spectra. The Vector model. The "Product Operators" formalism. Fundamental concepts of 2D NMR spectroscopy. Relaxation and Nuclear Overhauser Effect (NOE). Coherence selection: phase cycling cycle and field gradient pulses. The modern NMR spectrometer. Lab training.
Full programme
- Magnetic properties of nuclei: angular momentum and spin angular momentum. Microscopic magnetism. Correlation between magnetism and spin angular momentum.
- NMR Frequencies and Chemical shift. Linewidth and lineshape. Scalar coupling. The basic NMR experiment.
- Energy levels and NMR spectra. The spectrum for one spin. The energy levels for two coupled spins.
- The Vector model. The bulk magnetization. Larmor precession. Detection. Pulses. "On resonance" pulses. The rotating frame. The basic impulse-acquisition sequence. Calibration of pulses. The Spin-Echo experiment. Pulses of various phase. "Off-resonance" effetcs and "soft" pulses. Fourier Transformation and data processing. FID representation. Peaks linewidth and lineshape. FID manipulation. Zero filling.
- The "Product Operators" formalism. Product operators for one spin. Hamiltonians for spins and delays. Equation of motion. The spin-echo experiments with the product operators formalism. Product operators for two weakly coupled spins.
- Fundamental concepts of 2D NMR spectroscopy. 2D NMR experiments with coherence transfer mediated by J-coupling. COSY and DQF-COSY: pulses sequence and spectra interpretation. Double Quantum NMR Spectroscopy. Heterocorrelated 2D NMR spectroscopy. HMQC, HSQC and HMBC experiments: pulses sequence and spectra interpretation. 2D TOCSY NMR experiment: pulses sequence and spectra interpretation.
- Relaxation and Nuclear Overhauser Effect (NOE). The origin of the nuclear relaxation phenomenon. Mechanisms of relaxation. Correlation time. Population of the states. Longitudinal relaxation of isolated spins. Dipolar longitudinal relaxation of two spins. Cross-relaxation. Relaxation due to chemical shift anisotropy.
- NOEDif, NOESY and ROESY experiments: pulses sequence and spectra interpretation
- Coherence selection: phase cycling cycle and field gradient pulses. Order of coherence. Coherence transfer pathways. Frequency discrimination and peak shape.
- The modern NMR spectrometer. Magnet and Probe, Lock Channel, Shim and homogeneity of the magnetic field. RF synthesizer, amplifier and duplexer. Receiver and Quadrature detection. Analogue to digital convertor (ADC). Limits of digitization.
- Lab training: 1D NMR spectra acquisition (1H and 13CD). 2D COSY spectra acquisition. 2D NMR heterocorrelated HSQC spectra aquisition.
Bibliography
Recommended book:
J. Keeler, “Understanding NMR Spectroscopy”, 2nd edition, Wiley, 2010.
Suggested readings:
- N. E. Jacobsen "NMR Spectroscopy Explained: Simplified Theory, Applications and Examples for Organic Chemistry and Structural Biology, Wiley, 2007;
- M. H. Levitt "Spin Dynamics", Wiley, 2001.
Teaching methods
The course will be mainly based on front lessons and possible class exercises. Practical training on NMR instruments is also provided.
Assessment methods and criteria
Oral exam and written exercises.
Other information
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