AUTOMATIC PHASE CORRECTION FOR NMR SPECTRA-CONNECTING LINE OF EQUALLY SPACED POINTS(CLESP)

Abstract

Abstract:

A novel automatic phase correction method, CLESP, for NMR spectra based on DISPA circle is described in this paper. The phase angles of peaks are determined from the slope of the line connecting two peak points with equal data point density on each side of the peak on the complex plane. The calculated phase angles of the peaks are then used to extract the zero-order and first-order phase correction for the full spectrum by linear regression. In addition to the advantages of being non-iterative, fast, accurate, straightforward, easy to implement, and applicable to partial peaks, CLESP is robust with respect to noise, baseline distortion, peak overlaps, and poor digitization of NMR signals. CLESP algorithm has been successfully implemented in ECNMR , a home-made NMR data-processing software.

Key words: NMR, automatic phase correction, CLESP, DISPA

CLC Number:

O482.53

WANG Chao, HUANG Ying-Ying, YANG Guang. AUTOMATIC PHASE CORRECTION FOR NMR SPECTRA-CONNECTING LINE OF EQUALLY SPACED POINTS(CLESP)[J]. Chinese Journal of Magnetic Resonance, 2004, 21(4): 445-457.

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