cleanHMBC pulse sequence program

#  P. Würtz, P.Permi, N.C. Nielsen and O.W. Sørensen:
Clean HMBC: Suppression of strong-coupling induced artifacts in HMBC spectra
J. Magn. Reson.  (2008)

Echo/Antiecho gradient selection
uses initial and terminal low-pass J-filter for suppression of one-bond correlations including strong copuling induced artefacts.

Using decoupler channel 1 for X-pulses
Flags:
 presat	y:   presaturation during relaxation delay
        n:   no presaturation during relaxation delay

Low pass J filtering:
 lpjf     1-4: Order of initial low pass J filter (default:1)
 mboblpjf 1-3: Order of terminal low pass J filter (default:2)

Pulses and Powers:
 pw	90 degrees transmitter
 pwx	90 degrees decoupler 1
 pwlvl	90 degrees transmitter hard pulse power level
 pwxlvl	power level for decoupler high power
 tpwr   transmitter high power level
 satpwr	power level for saturation of solvent signal using transmitter
        during relaxation delay
 satdly	duration of presaturation
 satfrq	presaturation offset
altgrad	flag to use an alternative gradient scheme

Coupling constants
 Jmin smallest 1J(XH) for LPJF setting
 Jmax largest 1J(XH) for LPJF setting
 Jxh optimal 1J(XH) for strong coupling artefact suppression.
	Set to the average of Jmin and Jmax. You can however,
	alter this value if for instance you have one or two
        carbons with radically different 1J(CH) and you don't mind having
        more crosstalk for these. In this case set to the average
        of the 1J(CH)s of the rest of the spectrum.

Delays
 DELTA  HMBC evolution delay

Gradient settings
 gt1     length of the gradients used ca. 1msec
 gzlvl1  max size of gradients.for J filter
 gzlvl2  max size of gradients.for coherence selection
 gstab   gradient recovery delay
altgrad	flag to use an alternative gradient scheme

Other settings
 array='phase' (for processing with VNMR )
 MRC flag to select the gradient scheme of Nyberg & Sørensen, MRC 2006. (not recommended)

Processing as standard HMBC echo/antiecho processing:
 clean-HMBC: wft2da or wft2d(1,0,-1,0,0,1,0,-1)

 VnmrJ release 25/05/2008 by Peter Würtz

Tested on Vnmr6.1C:Inova 500 and Inova 600:Solaris acquisition host (Works OK)
Tested on VnmrJ:Inova 500 and Inova 600:Solaris acquisition host (Works OK)
To use on Vnmr6.1C change 'psg_abort' to 'abort' in the pulse sequence code.

Disclaimer:
Disclaimer for NMR pulse sequences from the Finnish National Biological NMR laboratory, University of Helsinki. Please pay attention to the requirements of your system, when implementing pulse sequences from this site.
Pulse sequences on this web site are tested and working on our spectrometers.
However, adjustments in pulse program syntax and/or parameter sets may be necessary on other hardware configurations or systems.

The Finnish National Biological NMR laboratory, the Institute of Biotechnology and the University of Helsinki does not make any warranties with respect to the software. In no event will the Finnish National Biological NMR laboratory be liable for any loss, damages of any nature arising or relating to the use or performance of the software.