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dc.contributor.advisorSuryaprakash, N
dc.contributor.authorBaishya, Bikash
dc.date.accessioned2010-07-28T10:09:47Z
dc.date.accessioned2018-07-30T14:47:44Z
dc.date.available2010-07-28T10:09:47Z
dc.date.available2018-07-30T14:47:44Z
dc.date.issued2010-07-28
dc.date.submitted2008-05
dc.identifier.urihttp://etd.iisc.ac.in/handle/2005/793
dc.description.abstractSpin selective MQ-SQ correlation has been demonstrated by either selective pulses in homo-nuclear spin systems in isotropic and weakly orienting chiral media or by nonselective pulses in hetero-nuclear spin systems in strongly aligned media. As a consequence of the spin selective correlation, the coherence transfer pathway from MQ to SQ is spin state selective. This two dimensional approach enables the utilization of the passive couplings (remote couplings) to break a complex one dimensional spectrum into many sub spectra. Each sub spectrum contains fewer transitions and hence fewer couplings (active couplings). The role of the passive couplings is to displace the sub spectra and measurement of the displacements taking into account their relative tilt provides the magnitude of the passive couplings along with relative signs. Further possibility of a spin state selective MQ-SQ resolved experiment to determine very small remote couplings otherwise buried within linewidth in one dimensional spectrum has been demonstrated. The resolution of the multiple quantum spectrum in indirect dimension has also been exploited to separate the sub spectra. The technique renders the analysis of complex spectrum in isotropic system much simpler. The potentialities of the technique have also been demonstrated for discrimination of optical enantiomers and derivation of the residual dipolar couplings from very complicated spectrum. The second order spectrum in strongly aligned media restrict selective excitation, however in hetero-nuclear spin system the nonselective pulses on protons do not interact with the hetero-nuclear spins. Thus the weakly coupled part of a strongly coupled spectrum has been exploited for simplifying the second order spectrum and thereby its analysis. Thus several methodologies derived from spin selective correlation has been demonstrated. Enantiopure spectrum has been recorded from a mixture of R and S enantiomers by a novel pulse scheme called Double Quantum Selective Refocusing Experiment. The dipolar coupled methyl protons in weakly orienting media are utilized. The selective excitation of double quantum coherence reduces the three spin system into a two spin system and remote couplings are refocused which otherwise leads to broadening. The sum of passive couplings being different for the enantiomers resolution in the DQ dimension is enhanced and thereby their discrimination. Finally several decoupling schemes has been compared in the indirect dimension of HSQC experiment to resolve 13C satellite spectra otherwise buried within line width for increased confidence in determining hetero-nuclear framework information.en_US
dc.language.isoen_USen_US
dc.relation.ispartofseriesG22331en_US
dc.subjectSpin (Physics)en_US
dc.subjectNuclear Magnetic Resonanceen_US
dc.subjectQuantum Nuclear Magnetic Resonanceen_US
dc.subjectSpectral Simplificationen_US
dc.subjectNuclear Magnetic Resonance Spectroscopyen_US
dc.subjectSpin Selective Multiple Quantum NMR (SS-MQNMR)en_US
dc.subjectEnantiomers - NMR Spectraen_US
dc.subjectDouble Quantum Excited Selective Refocusing (DQ-SERF)en_US
dc.subjectMultiple Quantum Coherenceen_US
dc.subjectThermotropic Liquid Crystalsen_US
dc.subject13C-1H HSQCen_US
dc.subject.classificationMagnetismen_US
dc.titleSpectral Simplification In Scalar And Dipolar Coupled Spins Using Multiple Quantum NMR : Developments Of Novel Methodologiesen_US
dc.typeThesisen_US
dc.degree.namePhDen_US
dc.degree.levelDoctoralen_US
dc.degree.disciplineFaculty of Scienceen_US


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