2D 103Rh frequency wrong
I have run a 1H-103Rh HMQC on [Rh(acac)(cod)] and found the chemical shift of the 103Rh to be -7023 ppm. The frequency of the 103Rh was first obtained by running a paropt on the "decp90" pulse program and changing O2 in order to decouple the 103Rh. When I found the frequency at which the 103Rh decouple, I used that value for O2 in the 2D 1H-103Rh HMQC. However, I am sure that this value of -7203 ppm is incorrect, since all the literature references to 103Rh NMR states that the chemical shift range for 103Rh is between -2000 and 10000 ppm. Also, [Rh(acac)(cod)] is given in literature as having a chemical shift of +1287 ppm.
I know that the peak is not folded, since I acquired a spectrum with the exactly the same parameters, but with O2p at 1000 ppm, but then I don't see any 1H-103Rh correlation. I am obviously doing something wrong, but can't figure out what. Have anyone encountered this with any X nuclei? The data were acquired on our 600 MHz Bruker Avance II, using a 5 mm TBI 1H/31P/BB inverse probe.
Any advice on the matter will be appreciated.
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