Methylene-Only Subspectra in 13C CPMAS Using a New Double Quantum Filtering Sequence

Paolo Rossi, Raju Subramanian, Gerard Harbison

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Methodology for the assignment of 13C CPMAS spectra is still in its infancy. Previous methods of CPMAS spectral editing have utilized differences in the strength of the 13C-1H dipolar interaction or the rate and spin thermodynamics of crosspolarization from protons to carbon, to differentiate between quaternary, tertiary, and methylene carbons. We introduce a different approach, which is based on the fact that double-quantum coherence develops between the protons of a methylene group considerably faster than between most other proton spin pairs in an organic solid. We generate this coherence, filter it, convert it back to single quantum, and then crosspolarize selectively to carbon, followed by a short period of reversed crosspolarization to null out unwanted coherence generated from longer distance spin pairs. The sequence has been named DQCP. While the signal-to-noise of this method is poorer than ordinary CP, it is comparable to previous methods for generating methylene-only spectra, and the technique is straight-forward and easy to implement,

Original languageEnglish (US)
Pages (from-to)159-163
Number of pages5
JournalJournal of Magnetic Resonance
Volume141
Issue number1
DOIs
StatePublished - Jan 1 1999

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methylene
Protons
Carbon
protons
carbon
organic solids
editing
Thermodynamics
Noise
methodology
filters
thermodynamics
interactions

ASJC Scopus subject areas

  • Biophysics
  • Biochemistry
  • Nuclear and High Energy Physics
  • Condensed Matter Physics

Cite this

Methylene-Only Subspectra in 13C CPMAS Using a New Double Quantum Filtering Sequence. / Rossi, Paolo; Subramanian, Raju; Harbison, Gerard.

In: Journal of Magnetic Resonance, Vol. 141, No. 1, 01.01.1999, p. 159-163.

Research output: Contribution to journalArticle

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