... A6 C-ab 37.8 21.7 19.5 24.8 10.6 a 6 in ppm from TMS, solvent CD,CI,. A6 Ca=6 Ca-6 C'-a @ Heyden & Son Ltd, 1980 ORGANIC MAGNETIC RESONANCE, VOL. 14, NO. 5, 1980 351 Page 4. J. P. BEGUE AND D. BONNET-DELPON Table 5. m Charges in ions 8 (in e-) ...