Varian Solid-State NMR - Useful Conversions; Figure 15. Pulse Sequence for Measuring H T

2.11 Useful Conversions
01-999162-00 C0402 VNMR 6.1C User Guide: Solid-State NMR 44
1
H T
1
Through
13
C Cross-Polarization
l
H T
1
can be measured using the XPOLAR1 pulse sequence by setting it up to perform a
standard inversion-recovery experiment on the protons followed by cross-polarization of
the remain
1
H magnetization to the carbons. Figure 15 illustrates the pulse sequence.
2.11 Useful Conversions
Convert from 90° pulse width to γH:
Convert from field strength in gauss to field strength in gauss:
1
H: γH (kHz) ≈ 4.3 * γH (gauss)
13
C: γH (kHz) ≈ γH (gauss)
Convert from rf fields to power levels:
P (watts)
∝ (γH)
2
Figure 15. Pulse Sequence for Measuring
l
H T
1
13
C
xpol='y'
1
H
cntct
d1
p180
d2
pw
(crossp)
(dipolr)
cntct
(tpwrm)
γH
2
kHz()
250
90°pulsewidth
--------------------------------------
µs()=