Thanks to everyone who gave me a big hand in acquiring Sn119 NMR spectrum!
Just for one day posting my requirement, I have received 13 responses. What
a mazing! I tried most of suggestions, and finaly, the problem was solved
as this : I reduced the acquisation time to 0.1s and relaxation delay to
0.5s, the peaks appeared at about -700 ppm! I believe that due to a very
short T1 of Sn(II), no signal can be observed when acquisation time too
long (it was 0.6s before). This credit should give to Dr. Rachael A. T.
Grould in 3M Corporate. Other comments are also very helpful. Thanks to
everybody again!
Qing Ning