The spatial magnetic properties, through-space NMR shieldings (TSNMRS), of isolated as well as B–C bond length varied model compounds (BR₃ trapped NHCs) have been calculated using the GIAO perturbation method employing the nucleus independent chemical shift (NICS) concept and the results visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. The TSNMRS values (actually the anisotropy effects measurable in ¹H NMR spectroscopy) are employed to qualify and quantify the present dative vs. coordinative bond character of the boron−carbon bond in the trapped NHCs. Results are confirmed by bond lengths and ¹¹B/¹³C chemical shift variations in the BR₃ trapped NHCs.

已使用GIAO扰动方法，采用核独立化学位移（NICS），计算了分离的以及B–C键长变化的模型化合物（BR ₃捕获的NHC）的空间磁特性，通过空间NMR屏蔽（TSNMRS）。概念和结果可视化为各种尺寸和方向的等化学屏蔽表面（ICSS）。TSNMRS值（实际上是在¹ H NMR光谱中可测量的各向异性效应）用于鉴定和定量所捕获的NHC中硼碳键的当前键与配位键的特征。BR ₃中的键长和¹¹ B / ¹³ C化学位移的变化证实了结果 被困的NHC。