Referring to Figure 18-19 , the absorbance profile shows several peaks, which correspond to electronic transition
A. the pi and pi* orbitals
B. molecular orbital theory
C. the HOMO and the LUMO
D. lowest unoccupied electronic level, and then the next higher electronic level, etc.
E. vibrational and rotational coupling with the electronic levels.
F. lowest unoccupied electronic energy level, but different vibrational levels.