School of Chemistry, College of Science, University of Tehran, Tehran, Iran.
Phys Chem Chem Phys. 2010 Oct 21;12(39):12630-7. doi: 10.1039/c004254d. Epub 2010 Aug 23.
The influence of electron density on the magnitude of non-nuclear magnetic shielding, NICS, is studied in detail by scanning the electron density vs. NICS(zz) (the out-of-plane component of NICS). This study sheds new light on the role of electron density on the magnitude of NICS. Scanning the electron density vs. NICS(zz) not only helps to discriminate the electronic ring currents operative in aromatic, nonaromatic and antiaromatic species, but also yields a measure to compare the strength of diatropic/paratropic currents in molecules with different ring sizes or different number of π electrons without relying on the methods of σ-π separation.
通过扫描电子密度与 NICS(zz)(NICS 的面外分量),详细研究了电子密度对非核磁场屏蔽(NICS)大小的影响。这项研究揭示了电子密度对 NICS 大小的影响。扫描电子密度与 NICS(zz)不仅有助于区分芳香族、非芳香族和反芳香族物种中起作用的电子环电流,而且还提供了一种衡量不同环大小或不同π电子数的分子中顺磁/反磁电流强度的方法,而无需依赖于σ-π分离的方法。