An emission of green visible light from the Cu2+ ion. The literature reports emission of blue visible light from the Cu+ ion. Choose the statement(s) below that best explain this data. (Select all that apply.)
A. The Cu+ ion has a greater effective nuclear charge than the Cu2+ ion.
B. Increasing the effective nuclear charge on an ion results in energy levels that are closer together.
C. Increasing the effective nuclear charge on an ion results in the emission of higher frequency photons.
D. Increasing the effective nuclear charge on an ion results in the emission of shorter wavel