Akira Fujino

35Cl-NQR of some chlorocarbons and oxochlorocarbons with a small ring.

35Cl-NQR of two chlorocarbons and six oxochlorocarbons, all having a small ring, were measured in the temperature range 77–300 K. The NQR line groups for the allylic and vinylic chlorine atoms appear separately in the five-membered ring compounds, whereas they are concentrated in a rather narrow region near 38 MHz in the four-membered ones. Perchlorocyclopropene possesses at least three crystal modifications at 77 K, the most stable one of which has only two lines in the temperature range examined. The line assignments, and the hyperconjugative effect in some of them, are discussed with reference to the CNDO/2 MO calculation data.