Composite sequences for efficient double-quantum Excitation over a range of spin coupling strengths

Thomas Barbara, R. Tycko, D. P. Weitekamp

Research output: Contribution to journalArticle

38 Scopus citations


It is demonstrated theoretically and experimentally that double-quantum coherence can be excited with nearly maximal efficiency over a large range of spin coupling strengths in NMR with the use of composite excitation sequences. Such sequences are shown to be directly constructible from existing composite π 2 pulses. In addition, a general procedure is given for converting a composite excitation sequence to an equivalent, reduced form that contains fewer rf pulses and simpler rf phase shifts. Experiments are performed on the proton pair of CH2Cl2 oriented in a liquid crystal solvent. Applications to quadrupolar spin-1 nuclei and other dynamically simple multilevel systems are discussed.

Original languageEnglish (US)
Pages (from-to)54-64
Number of pages11
JournalJournal of Magnetic Resonance (1969)
Issue number1
StatePublished - 1985
Externally publishedYes


Cite this