TBR - Energy for electron excitation

[loveoforganic]

In TBR Chem Passage XI, they present a data table that indicates that as you go down a column in the periodic table, the energy required to place the outermost electron in an excited state increases.

Is this data scientifically incorrect or is there something I'm missing? Further distance from the nucleus, easier to excite is what makes sense in my mind.

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[cheesier]

In TBR Chem Passage XI, they present a data table that indicates that as you go down a column in the periodic table, the energy required to place the outermost electron in an excited state increases.

Is this data scientifically incorrect or is there something I'm missing? Further distance from the nucleus, easier to excite is what makes sense in my mind.

I'm not 100% sure on this, but I think that you could think about it in relation to wavelengths.

Remember the Rydberg formula:

So as Z (atomic number) increases, the wavelength decreases.

We know that E=hc/λ. So as the wavelength decreases, energy required to excite the electron increases.


I also wanted to add that a larger atomic radius means an electron is easier to remove, but exciting it is different. It has to move to a higher energy orbital, and the orbitals get steeper in their energies moving from s to p to d to f. So s to p is a smaller jump than d to f.

 

[mzblue]

i think it's cuz ionization energy increases.

 

[Rabolisk]

i think it's cuz ionization energy increases.

I think not, because the opposite is true.

 

[loveoforganic]

So if we were to try to conceptualize why this might be, outside of formulae, could it be something along the lines of - the nucleus is still controlling an electron, decreasing its entropy relative to ionization, but it has relatively little electrostatic interaction with it, so the necessary energy to hold on to it must be fairly large.

y/n?