Iterative schemes for bilinear operators; application to spin decoupling.

A. J. Shaka, C. J. Lee and A. Pines

Department of Chemistry, University of California, Berkeley, California 94720, USA.

Materials and Chemical Sciences Division, Lawrence Berkeley Laboratory, Berkeley, California 94720, USA.

We extend the idea of iterative schemes from the single-spin to the two-spin-case. As an application we derive a new series of broadband heteronuclear decoupling sequences, called the DIPSI sequences. They give better quality decoupling of protons from carbon-13 than previous sequences like WALTZ-16 when there is scalar coupling among the protons. In the absence of such coupling, the DIPSI sequences offer the same high standard of performance as WALTZ-16, but over somewhat smaller bandwidths.