摘要:
**1**3 C NMR chemical shifts of the model compounds for ethylene-propylene (E-P) copolymer with a low ethylene content were calculated using the gamma-effect of **1**3C chemical shift and Mark's rotational isomeric state matrices of E-P copolymer. Observed **1**3C chemical shift differences for the carbons of interest were reasonably explained by the calculation. The magnitude of the gamma-effect was found to be sensitive to the change of the comonomer sequences. These estimated chemical shift differences are comparable to the stereosequence dependence of **1**3C chemical shifts.
摘要:
The effect of the lattice structure on the phase shifts of the conduction electrons near the Fermi level, due to scattering by a core hole or an impurity atom, has been evaluated. The resulting phase shift δ0 for sodium is found to be substantially lower than that reported previously. This should have an effect on the edge structure of L-band spectra of simple metals such as sodium.