Anisotropy of the 1H and 13C shielding tensors in chloroform

✍ Scribed by Juha Vaara; Kari Oikarine; Jukka Jokisaari; Juhani Lounila

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 639 KB
• Volume: 253
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(96)00188-1

✦ Synopsis

The anisotropies, Atr, of the ]H and 13C nuclear shielding tensors of chloroform were determined experimentally and theoretically. The liquid crystal NMR ENEMIX method gives Ao" c = --51.8 to --51.4 ppm in excellent agreement with ab initio GIAO SCF/MCSCF calculations resulting in -51 ppm, preferring the ENEMIX results for C to the ones based on spin-lattice relaxation. A theoretical model and further experiments imply that the deviation of the ENEMIX A o" H value from the calculated 7 ppm is caused by hydrogen bonding between CHC13 and the CmN groups of the liquid crystal ZLI 1167, which is usually considered an inert solvent.