Electronic delocalization in NC and NN bonds

For a series of compounds with NC or NN bonds, the CNDO/S parameterized calculations for Qπ, the electronic charge density on the nitrogen atom, and π bond orders Pπ provide evidence for the simultaneous dependence of the 15N chemical shift on both of these parameters. The multilinear regressions obtained produce high values for the regression coefficients. The results throw some light on the nitrogen lone pair delocalization mechanism.