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5 MULTINUCLEAR MEASUREMENT
5.2
METHOD OF MEASURING RARE SPIN NUCLEUS OF
SPIN 1/2
Since a rare spin system is easy to treat due to its small interaction compared with other
nuclei, it is the kind of nucleus most generally measured using the solid-state NMR. Be-
cause these nuclei are spin 1/2, there is no nuclear quadrupole interaction. Moreover,
since the homonuclear dipole interaction is also weak, MAS (Magic Angle Spinning) can
eliminate anisotropic interactions other than the C-H heteronuclear dipole interaction.
Heteronuclear Dipolar Decoupling can eliminate the C-H heteronuclear dipole interaction.
A high-resolution spectrum is obtained by combining MAS and Heteronuclear Dipolar
Decoupling. Moreover, a sample containing the
method to improve the sensitivity and accumulation efficiency.
Usually, samples of rare spin systems are measured by using the single pulse method with
decoupling or the CPMAS method.
Mainly used sequence
• single_pulse_solid.jxp
• single_pulse_dec_solid. jxp
• cpmas. jxp
5.3
METHOD OF MEASURING
In order to measure
caused by the strong homonuclear dipolar interaction. Since the homonuclear dipolar in-
teraction of
spectrum. However, in the
information can be obtained by performing MAS above 15 kHz. Moreover, for a sample
with a low density of
spectrum at several kilohertz, and useful information may be obtained. The signal obser-
vation of the sample may be difficult due to the background signal originating in the
probe when the
served by eliminating the background signal using the DEPTH2 method.
Usually, a sample of an abundant-spin system is measured by using the single-pulse or
the depth2 method.
Mainly used sequence
• single_pulse_solid. jxp
5-2
1
H and
19
F, it is necessary to suppress the broadening of the line
1
H and
19
F is very strong, MAS of about 10 kHz cannot give a high-resolution
19
F nucleus, since the range of chemical shift is wide, useful
H, such as inorganic materials, MAS can give a high-resolution
1
1
H or
19
F nucleus is observed. In this case, the target signal can be ob-
1
H nucleus is measured by the CPMAS
1
19
H/
F
NMECAXS_V50-SLD-2
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