The NQR of14N of the sngbnd;CN group in some benzonitriles with electronhyphen;releasing as well as electronhyphen;withdrawingparahyphen;substituent groups, has been studied. The experimentally obtained values oflpar;e2qQrpar;z, the quadrupole coupling constant, and ofGgr;, the asymmetry parameter of the electric field gradient, are discussed on the basis of the Townes and Dailey theory. The discussion may be developed further, with some assumptions, to obtain the electron populations of the twophyphen;type orbitals describing thepgr;bonds between the nitrogen and the carbon atoms of the cyano group. The variations of such electron populations when changing theparasubstituent is obtained. A good correlation was also found between the values of the electron populations of thephyphen;type orbital orthogonal to the benzene ring and the variations of the electron distribution on the ring, as described by the Hammettsgr;values for the correspondingparahyphen;substituent groups.
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