I wanted to thank all of you who responded to this email. As it turns out,
with TopSpin 1.3 there is a "new" file in exp/stan/nmr/lists called
solvents.auto. There are only 6 solvents listed in this file that ships
with the release. Auto lock-in is only performed on solvents listed in this
file and methanol is not in there by default.hence the problems I was
experiencing with methanol and auto lock-in. Since methanol was not listed,
manual lock-in was attempted which needs of course an accurate FIELD value
since the capture range I believe is +/- 10 units. I had been in the habit
of including a 25 unit offset in my field setting and so manual lock-in on
methanol failed as well without an entry in the Field Correction column of
the edlock table. The developers at Bruker tell me that this approach will
be changed with TopSpin 2.0.
Best Wishes,
Mike
----------------------------------------------------------------------------
----------
Michael D. Lumsden, Ph.D.
NMR Facility Coordinator
Room 428, Atlantic Region Magnetic Resonance Centre
Department of Chemistry, Dalhousie University
Halifax, Nova Scotia, Canada
B3H 4J3
phone: 902-494-1635
FAX: 902-494-1310
http://armrc.chemistry.dal.ca
> _____________________________________________
> From: Mike Lumsden [mailto:mike.lumsden@dal.ca]
> Sent: June 21, 2006 2:30 PM
> To: Bruker Users List (bruker-users-mail@purcell.cchem.berkeley.edu)
> Cc: Katherine Nancy Robertson (kathy@dal.ca)
> Subject: Autolocking - TopSpin vs XWIN
>
> Dear Bruker Users,
>
> I wanted to ask about an issue we've had with autolocking under the
> TopSpin version of ICONNMR automation recently. While we were running
> xwin 3.5 and to deal with autolocking on solvents with more than 1
> deuterium resonance, I used to deliberately set my BSMS field value to
> about 25 units or so less than what was really required. Somewhere along
> the way, I heard/read that the auto lockin procedure will always "look" in
> the same direction. So as long as my field value was just less than the
> correct deuterium resonance, all was well. Thus, with ICONNMR that was
> bundled with the NMRSuite software, I never ever had to use the "-noauto"
> flag for any solvent.
>
> That all changed when we recently upgraded to TopSpin 1.3. I am running
> the most recent ICON-NMR version (4.0.3 Build 5 under Windows 2000). When
> we simply carried over our old edlock table from xwin, we could not auto
> lockin on CD3OD whereas all other solvents, which had only 1 resonance,
> worked seamlessly. Methanol failed every single time on many different
> samples even though my BSMS field value was still set 25 units below the
> right peak. Today I added an entry in the Field Correction column of the
> edlock table for methanol and, combined with using the -noauto flag,
> locking on methanol with ICONNMR automation works again.
>
> So what I'm really wondering is
> a) Does anybody have a feel for why I could get away with this under xwin
> but no longer under TopSpin?
> b) Should I get busy now and add a Field Correction entry for each solvent
> in edlock that has more than 1 resonance and activate the -noauto switch
> in ICON as well?
> c) Is it still advisable to set the BSMS FIELD to something less than
> what the actual number should be?
>
> Thanks for your insights!
> Mike
>
>
> --------------------------------------------------------------------------
> ------------
> Michael D. Lumsden, Ph.D.
> NMR Facility Coordinator
> Room 428, Atlantic Region Magnetic Resonance Centre
> Department of Chemistry, Dalhousie University
> Halifax, Nova Scotia, Canada
> B3H 4J3
>
> phone: 902-494-1635
> FAX: 902-494-1310
> http://armrc.chemistry.dal.ca
>
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