Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.
DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.
Right angles: In solid-state magic-angle spinning (MAS) NMR spectra, the line widths of carbonyl carbon atoms in polycryst. cholesteryl acetate are as narrow as 0.039 ppm if the magic angle is adjusted very accurately, i.e., within +-0.004 Deg. The line broadening obsd. for slightly miss-set angles is mostly due to residual chem. shift anisotropy (CSA) interactions. Long spin-echo life times up to T'2 = 3.6 s open the way to sophisticated NMR methods. [on SciFinder (R)]