Nitropyridines dipole moments

Fig. 17. (a) Orientation of molecular dipole moments in 3-methyl-4-nitropyridine. Y-oxide fih molecular dipole moment from direct integration methods fi2, from multipolar model and Hj from semi-empirical calculation, (b) Electrostatic potential around the molecule in the plane of ring atoms. Contours at 0.2kcal/mol (reproduced with permission from Hamazaoui et al. [79]). 

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