ratio of gradients in HMQC experiments (1h-13C)

Jose Martins (jose@HNMR.vub.ac.be)
Mon, 11 Sep 95 16:20:39 +0200

Dear Bummers,

When using pulsed field gradients (PFG) in HMQC experiments,
one usually applies three PFG's located as follows:
G1 just before the 1H(180) in the middle of t1.
G2 just after the 1H(180) in the middle of t1.
G3 just after the last 13C(90) pulse (in case of a 1H-{13C} HMQC).

Now there are many diffrent ways of choosing the relative strenghts
of these gradients (see for instance Ruiz-Cabello et al. in J. Magn.
Res. 98, 207 (1992)), but the combinations which are suggested in the
Bruker pulse programs for HMQC we have seems not to be one of those
reported in the literature. Many use 20:20:10 or 50:30:0, but
Bruker uses 50:30:40. Are there any good reasons why one should choose
these instead of those reported in literature? Or is it juster a matter
of taste?

Appreciate any comments!

jose
Jose Martins
High Resolution NMR Centre
Vrije Universiteit Brussel
phone: 32-2-629-33-05
fax : 32-2-629-33-04
e-mail jose@hnmr.vub.ac.be
jose@bionmr1.rug.ac.be