Hello Weixing Zhang,
I am not sure what the four small signals are.
The answer to your question on the symmmetry of the
C13 satellites is this. You are seeing a C13 induced
isotope shift on the protons coupling with C13. The
chemical shift of the H1(C12) is set at 0hz as you said.
The chemical shift of H1(C13) is -1.5hz and the Jhc is
215hz symmetrically distributed about that signal.
Allan Kershaw
Director of NMR Instrumentation
University of Southern California
Phone 213 740-6376
email allan_at_kershaw.usc.edu
WWW
http://nmrnet.usc.edu
Hello everybody:
I recently got a nonspin lineshape spectrum with extra peaks.
If I set the main CHCl3 peak at 0 Hz, I saw extra small peaks
at -111 Hz, -57 Hz, 57 Hz, and 111 Hz. Their intensity is about half
of the C13 satellite peaks. What might be the problem?
I closely looked at the normal lineshape spectrum. The two
C13 satellite peaks are located at -109 Hz and 106 Hz.
Does anybody know why they are not symmetrical (-107.5, 107.5 Hz).
Thanks,
Weixing Zhang, Ph.D.
Department of Structural Biology
St. Jude Children's Research Hospital
Voice: (901)495-3169
FAX: (901)495-3032
Received on Wed Jan 23 2002 - 17:13:35 MST