Jul 5, 2009

Tips, Tricks

PROBE TUNING
- first tune 1H, then X (proton tune will affect X)
- make list of X-tuning micrometer settings
- start 50 MHz wbsw, then <10 Mhz [Do not change matching without proper tuning position - you can loose any response from probe] (remove filterboxes - fake resonances due to circuits in filters)
- empty probe may change tuning up to 10 MHz More......

B1 homogeneity BL4

B1 field profile for BL4 :








(c) F. Ziarelli et al. / Journal of Magnetic Resonance 188 (2007) 260–266 More......

May 23, 2009

4mm coil after rotor crash on 10kHz

More......

May 3, 2009

SS NMR references

Some references for solid-state NMR


http://upload.wikimedia.org/wikipedia/commons/a/a5/Glycine-zwitterion-2D-skeletal.png
13C   (C=O)
α-Glycine 176.5ppm
γ-Glycine 174.5ppm

15N
α-Glycine 32.3ppm
γ-Glycine 32.9ppm

α-Glycine   T=296K
1H T1=0.25 s
1H T1ρ=44 ms
13C T1=12 s (C=O)
13C T1=11 s (NCH2)
13C T1ρ=180 ms (C=O)
13C T1ρ=43 ms (NCH2)
15N T1=240 ms
15N T1ρ=93 ms

γ-Glycine   T=296K
1H T1=4 s
1H T1ρ=4.1 ms
13C T1=55 s (C=O)
13C T1=22 s (NCH2)
13C T1ρ=270 ms (C=O)
13C T1ρ=53 ms (NCH2)
15N T1=150 ms
15N T1ρ=18 ms

γ-Glycine - not for cp setup (short T1ρ 1H)!!!

prep. α-Glycine:  precipitate with acetone from aq. solution

29Si
Q8M8 - +11.7 ppm
(+11.77 +11.72 +11.51 -108.36 -108.64 -109.36 -109.71)

splitting - deformation Q8 cube and fixed M orientations.
(in liq +12.4 -108.6)




*D1>10s ,cpmas setup


27Al
AlCl3*6H2O - o ppm (T1=11s)
Al(NO3)3 - 0 ppm
Al(D2O)6Cl3 - 0 ppm

35Cl(sensitivity) 37Cl(resolution)
NaCl in D2O - 0 ppm


195Pt
K2PtCl6 - 0 ppm
Na2PtCl6 - 0 ppm (D1>6s, hpdec)
19F
(CF2CF2)n - -122.0 ppm (PTFE insert) More......