Spin-Noise-Detected Two-Dimensional Fourier-Transform NMR Spectroscopy

*S Supporting Information ABSTRACT: We introduce two-dimensional NMR spectroscopy detected by recording and processing the noise originating from nuclei that have not been subjected to any radio frequency excitation. The method relies on cross-correlation of two noise blocks that bracket the evolution and mixing periods. While the sensitivity of the experiment is low in conventional NMR setups, spin-noise-detected NMR spectroscopy has great potential for use with extremely small numbers of spins, thereby opening a way to nanoscale multidimensional NMR spectroscopy. SECTION: Spectroscopy, Photochemistry, and Excited States Felix Bloch predicted the existence of spin-noise in 1946.1Experimental verification had to wait until 19852 due to the low amplitude of the phenomenon. Recent progress in magnetic resonance instrumentation, in particular, cryogenically cooled probes3 and force-detected magnetic resonance as well as extensive work on one-dimensional spin-noise spectrosco