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Proton NMR acquisition and processing conditions

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Proton NMR acquisition and processing conditions Powered By Docstoc
					Typical parameters used to record 13C NMR spectra on the the 250,
DPX-400, Avance-400 and Avance-500.

DPX-400 (Old-400 in F114a)
NMR spectra were obtained on a Bruker DPX-400 MHz spectrometer operating at
100.61 MHz for carbon and 400.13 MHz for proton decoupling, employing a high-
resolution dual(1H 13C) gradients probe. The zgpg30 pulse program was used, which
employs a direct 30° pulse on carbon with waltz16 decoupling during acquisition and
a relaxation delay of 1 second. Spectra were recorded over a sweep width of 250 ppm
(25,252 Hz) with 64k time domain data points giving an acquisition time of 1.30
seconds, exponential function(LB=1) applied, Fourier transformed using 128k data
points and referenced to an internal TMS standard at 0.0 ppm. Acquisitions are
automatically halted when the signal to noise ratio reached 150 for magnitude-
calculation spectra (corresponding to ~100-120 for the phase-corrected spectra).

Avanve-400 ultra shield (New-400 in F113)
NMR spectra were obtained on a Bruker ultra-shield Av-400 spectrometer operating
at100.61 MHz for carbon and 400.13 MHz for protons, employing a 5mm high-
resolution broad-band ATMA gradients probe. The zgpg30 pulse program was used,
which employs a direct 30° pulse on carbon with waltz16 decoupling during
acquisition and a relaxation delay of 1 second. Spectra were recorded over a sweep
width of 250 ppm (25252 Hz) with 64k time domain data points giving an acquisition
time of 1.30 seconds, exponential function(LB=1) applied, Fourier transformed using
128k data points and referenced to an internal TMS standard at 0.0 ppm. Acquisitions
are automatically halted when the signal to noise ratio reached 150 for magnitude-
calculation spectra (corresponding to ~100-120 for the phase corrected spectra).

Avanve-500 (In F202)
NMR spectra were obtained on a Bruker Avance-500 spectrometer operating at
125.76 MHz for carbon and 500.13 MHz for protons, employing a 5mm high-
resolution broad-band ordinary geometry probe. Spectra were recorded using the
zgpg30 pulse program which employs a direct 30° pulse on carbon with waltz16
decoupling during acquisition and a relaxation delay of 1 second, with 13C P90 = 10.0
μs covering a sweep width of 250.0 ppm (31,250 Hz) with 128k time domain data
points giving an acquisition time of 2.0 seconds, exponential function(LB=1) applied,
Fourier transformed using 128k data points and referenced to an internal TMS
standard at 0.0 ppm.

AC-250
NMR spectra were obtained on a Bruker AC-250 MHz spectrometer operating at 62.9
MHz for carbon and 250.13 MHz for CPD proton decoupling, employing a 5 mm
high-resolution broad-band HX probe. Spectra were recorded over a sweep width of
256 ppm (16130 Hz) with 32K time domain data points giving an acquisition time of
1.02 seconds, Fourier transformed using 64K data points and referenced to an internal
TMS standard at 0.0 ppm.

				
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posted:2/23/2010
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