C13–H and X—H Coupling Constants for Compounds of the Type X(CH3)4

摘要: From high‐resolution proton magnetic resonance experiments, absolute magnitudes of JC13–H and JX–C–H have been determined for compounds the type X(CH3)4, where X=Si, Ge, Sn, Pb. The values yield s characters carbon orbitals in C–H C—X bonds as well Juan—Gutowsky character affinity ΔX. Rough calculations based on Fermi contact term give widely varying results depending value effective charge used. A straight line correlation with n3 can be explained crudely basis term.