The compound (C₆H₅)₃ As is reported (J. Mol. Spectr. 5, 118-132 (1960)) to have two absorption bands, one near 270-m and a second around 230nm. One band is due the ->* transition of the phenyl ring and the other is a charge-transfer transition from the lone pair electrons on the arsenic to the ring. The 230-nm band is solvent dependent and the 270-nm band is not.

Which band do you think is the ->* band?

What effect would substitution of one of the phenyl groups by CF₃ have on the frequency of the charge-transfer transition?

In which of the following compounds would the charge-transfer band occur at the highest frequency (C₆H₆)₃P, (C₆H₆)₃Sb, or (C₆H₆)₃Bi?