Abstract
The titled spectra have been determined at 75 °C. The (M+H)+ ion intensities for methylbenzenes decrease linearly with the number of methyl substituents. The (M+H)+ ion intensities for dialkylbenzenes decrease in the order o->m->p-, while those of trimethylbenzenes decrease in the order 1,2,3-> 1,3,5->1,2,4-, and those of tetramethylbenzenes decrease in the order 1,2,3,4->1,2,3,5->1,2,4,5-.