NNR IN RAPIDLY ROTATED METALS By - Nottingham eTheses ...

and
-7-
Vd(t) f(w1)cos w't dw
Sao
- G(t)
.
If the nuclear lineshape is symmetric about w' -0, G(t) may be
rewritten in the form
(1.12)
G (t) 27r 1f (v')exp(-27riv'#)dv (1.13)
where v' a W'/21T. Hence, we have shown that the observed FID is
equivalent to the Fourier transform of the absorption lineshape.
It follows that the lineshape may be defined by the inverse Fourier
transform of the FID.
In the case where f(w') is asymmetric the lineshape is obtained
by including the two components of the transverse decay, along the
x* and y* axes, in the complex Fourier transform
f(w') 1 M* cos w't + M* sin w't dt
.. co
A similar result is achieved by shifting the detection frequency
by a value a (greater than the linewidth) away from wo, and record-
ing the decay component MM(t). It is then only necessary to
define the phase of My(t) in order to obtain the asymmetric spectrum
from a symmetric transform about a.
(2)