Lin Y, Ahn S, Murali N, Brey W, Bowers C R, Warren W S
Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Phys Rev Lett. 2000 Oct 23;85(17):3732-5. doi: 10.1103/PhysRevLett.85.3732.
Resistive or hybrid magnets can achieve substantially higher fields than those available in superconducting magnets, but their spatial homogeneity and temporal stability are unacceptable for high-resolution NMR. We show that modern stabilization and shimming technology, combined with detection of intermolecular zero-quantum coherences (iZQCs), can remove almost all of the effects of inhomogeneity and drifts, while retaining chemical shift differences and J couplings. In a 25-T electromagnet (1 kHz/s drift, 3 kHz linewidth over 1 cm(3)), iZQC detection removes >99% of the remaining inhomogeneity, to generate the first high-resolution liquid-state NMR spectra acquired at >1 GHz.
电阻磁体或混合磁体能够实现比超导磁体更高的磁场，但它们的空间均匀性和时间稳定性对于高分辨率核磁共振来说是不可接受的。我们表明，现代稳定和匀场技术与分子间零量子相干（iZQC）检测相结合，可以消除几乎所有不均匀性和漂移的影响，同时保留化学位移差异和J耦合。在一个25 T的电磁铁中（漂移为1 kHz/s，1 cm³范围内线宽为3 kHz），iZQC检测消除了>99%的剩余不均匀性，从而产生了在>1 GHz下采集的首批高分辨率液态核磁共振谱。
