A method of calculation of nuclear shieldings, in which localized molecular orbitals
associated with inner shell, bonding orbitals, and lone pairs have unique origins
for the calculation of
diamagnetic and
paramagnetic terms. With this method, satisfactory estimates of
NMR chemical shifts for elements in the first and second rows can be achieved in
ab initio calculations with basis sets of moderate size provided sufficiently accurate molecular
geometries are used.
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