Nuclear
Magnetic Resonance (NMR) crystallography is
a type method that uses primary NMR spectroscopy to find the structure of
different solid materials in the atomic scale. So, the solid-state NMR
spectroscopy will be used primarily, and possibly supplemented by quantum
chemistry calculations (e.g. density functional theory), powder diffraction
etc. If crystals are grown properly and uniquely, any crystallographic
method can generally be used to determine
the crystal structure and in case of organic compounds the molecular structures
and molecular packing. The main use of NMR crystallography is in determining micro crystalline materials
which are used to this method but not to X-ray, neutron and electron
diffraction. This is largely used because interactions that are short range are
measured in NMR crystallography.
NMR can now be used to refine diffraction results and, in
favorable cases, to solve crystal structures with minimal (or even no)
diffraction data. The increasing ability to relate chemical shifts (including
the tensor components) to the crystallographic location of relevant atoms in
the unit cell via computational methods has added significantly to the practice
of NMR crystallography. Diffraction experts will increasingly welcome NMR as an
allied technique in their structural analyses. Indeed, it may be that in the
future crystal structures will be determined by simultaneously fitting
diffraction patterns and NMR spectra.
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NMR
chemical shifts can distinguish between static and dynamic disorder in
crystalline materials and can be used to determine modes and rates of molecular
exchange motion. NMR crystallographic methods
are frequently used in combination with diffraction methods. Long-range order
is not a requirement for NMR studies of solids, and so NMR can offer advantages
for studying disorder, guest dynamics, and amorphous or heterogeneous systems.
For more details kindly go through: https://crystallography.materialsconferences.com/
Contact:
Jessica Mark
Program Manager | Crystallography Congress 2018
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