Nitrobenzene, geometry compared

Fig. 27. Concentration dependent intensity ratio of fluorescence band I (372 nm) and band III (383 nm) of pyrene solubilized by analogous polysoaps of different geometry, compared to their relative solubilization capacity for 4-hexyloxy-nitrobenzene. From top to bottom 59 ( head geometry), 60 ( mid tail geometry), 56 ( tail end ) data from [167, 343]...

Compare the geometry of para-nitroaniline to those of both aniline and nitrobenzene. Is there any evidence for push-pull resonance contributors Is there shortening of bonds to the amino and nitro groups Are the bonds in the ring localized Is the dipole moment for para-nitroaniline smaller, larger or about the same as the sum of the dipole moments for aniline and nitrobenzene What does your result say about the importance of push-pull resonance contributors ... 

Use Spartan View to obtain the dipole moments of aniline, nitrobenzene, and 4-nitro-aniline. Is the dipole moment of 4-nitroani ine the sum of the dipole moments of aniline and nitrobenzene Compare electrostatic potential maps and geometries for all three structures, and draw resonance structures for 4-nitroaniline that account for your observations. 

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