Zooming, a practical strategy for improving the quality of multidimensional NMR spectra

A method has been developed, which is termed "zooming," that provides high digital resolution in any region selected from an n-dimensional data set. The region selected can be of arbitrary size (any number of data points). In the zooming approach as implemented in the "ZOOM" computer program, the desired region of the frequency-domain spectrum is first extracted. Next, a "pseudo-FID" for the selected region is constructed by n-dimensional inverse Fourier transformation. The resulting time-domain data block is zero filled in n -dimensions and finally Fourier transformed back to the frequency domain. The basic principles behind the zooming approach are described, and its application to the analysis of 2D and 3D NMR data from proteins is demonstrated. Zooming is expected to be of even greater importance in the analysis of higher-dimensional NMR data where problems of acquisition and processing times and data storage space become more pronounced. The implementation described here is for spectra consisting of real or absolute-value data; at least one zero fill must have been applied in each dimension during the initial processing of the data.