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NMR (PG503). Workshop 1: Building blocks of liquid state NMR, product operator calculations. Dr Philip Williamson February 2009. Building block of liquid state NMR. 1 H/ 15 N INEPT. 1D 1 H Spectrum. HSQC. 1D 1 H NMR Spectrum. I 1x ( p /2). 1 H. H CS = W 1 I 1z.
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NMR (PG503) Workshop 1: Building blocks of liquid state NMR, product operator calculations Dr Philip Williamson February 2009
Building block of liquid state NMR 1H/15N INEPT 1D 1H Spectrum HSQC
1D 1H NMR Spectrum I1x(p/2) 1H HCS=W1I1z
1D 1H/15N INEPT NMR Spectrum I1y(p/2) I1x(p/2) t 1H HJ=2pJI1ZI2Z I2x(p/2) HCS=W1I1z+W2I2z • What value of t gives maximal 15N signal? • Does signal appear from anywhere else (15N?) • Why do we do this ????????? • What happens if the chemical shifts evolve during t? • What pulses can we apply to remove these effects?
1D 1H/15N INEPT NMR Spectrum I1x(p/2) I1x(p) I1y(p/2) t/2 t/2 1H H=2pJI1ZI2Z+W1I1z+W2I2z I2x(p) I2x(p/2) HCS=W1I1z+W2I2z • What happens if the chemical shifts evolve during t? • What pulses can we apply to remove these effects? • Why do we need two p pulses
1D 1H/15N HSQC NMR Spectrum I1x(p) t/2 t/2 I1x(p/2) I1y(p/2) I1x(p/2) I1y(p/2) t/2 t/2 1H t1/2 t1/2 H=2pJI1ZI2Z+W1I1z+W2I2z I1x(p/2) I2x(p) I1x(p/2) 2I1ZI2Y • What does the 2nd INEPT transfer do • What would be the effect of leaving out the p pulse on the proton during t1