ONE-DIMENSIONAL CHEMICAL-SHIFT MODULATED CORRELATION SPECTROSCOPY OF SINGLE-CRYSTALS

A simple 1D modulation method is presented for determining the spatial correlation of chemical shifts in two different single-crystal orient ations. This proposed chemical shift modulated correlation (CSMC) spec troscopy utilizes a Jeener pulse sequence to give 1D spectra containin g peaks that are amplitude modulated by the chemical shifts associated with the single-crystal's evolution orientation. Conversely, the spec tral frequencies in these 1D CSMC spectra designate the shifts in the crystal's orientation during the detection period. By observing the am plitude modulation of these spectral frequencies, the spatial correlat ion between the two chemical environments can be established for a spe cific nucleus from a single 1D spectrum. The CSMC procedure finishes b y acquiring a normal 1D static spectrum for the crystal oriented in th e evolution direction, thereby providing very accurate evolution frequ encies approximated by the amplitude modulation in the CSMC spectra. T he CSMC method improves the time efficiency over both the traditional goniometer method and the 2D chemical shift-chemical shift correlation method, and therefore is beneficial for the study of samples with lon ger T-1 values.