Term
| what does nuclear magnetic resonance spectroscopy give information on? |
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Definition
the structure of molecules in solution
it is an extremely powerful technique for characterisation. It is useful for simple organic compunds and large macromolecules
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Term
| when did High resolution Fourier Transform NMR spectrometers become available? |
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Definition
in the 1970's
the growth and application of FT-NMR techniques continues today
eg Magnetic resonance Imaging (MRI)
these are tomographic images using NMR methods |
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Term
| what did Bloch and Purcell first demonstrate about certain Hydrogen nuclei absorbing and emmiting radiation? |
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Definition
| they demonstrated that certain nuclei eg 1H will absorb and then emit electromagnetic radiation in the radio-frequency range WHEN placed in a strong magnetic field |
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Term
| name the four basic steps of an FT-NMR experiment |
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Definition
- Place sample in strong and uniform magnetic field
- Tune radiofrequency source to correct frequency band for type of nucleus eg 1H or 13C
- Excited nuclei by broad-band RF pulses
- Record RF the sample emits after each pulse
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Term
| why is the sample spun at ~20Hz? |
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Definition
| to reduce any effects due to inhomogeneity |
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