How does spin-orbit splitting also affect this or anomalous zeeman effect or decrease in spin when you move from Nitrogen to Oxygen?

Bad Teacher: The addition of the second electron into an already occupied orbital introduces repulsion between the electrons, thus it is easier to remove. that is why there is a dip in the ionization energy.

Bad Teacher: In oxygen, the last electron shares a doubly occupied p-orbital with an electron of opposing spin. The two electrons in the same orbital are closer together on average than two electrons in different orbitals, so that they shield each other from the nucleus more effectively and it is easier to remove one electron, resulting in a lower ionization energy.[2][14]

The problem is then you can't use the same explanation to explain Fluorine is higher ionization energy than Oxygen because you're also adding repulsions.

Bad Teacher:Stability of half-filled orbitals or completely filled orbitals.

This quote is using is arguing a point not building evidence for it.

I've tried studying spin and that doesn't explain it.

I tried using term symbols. Can you compare ionization energies of different atoms using that via Highest spin highest J?

I am trying to understand something i had red on several sources about hormonal imitators in humans.

I had learnt that many new cooking appliances are now sold as "BPA Free" since that substance is said to imitate estrogen, the female hormone.

i also have Asperger syndrome, i am male, i had took knowledge about a theory claiming we use to have extremely male brains after the, likely, pre-birth exposure to either abnormally high ammounts of testosterone or some sort of testosterone emulator in the environment.

I am not a chemist, my fields are robotics, electronics and some coding, however, i feel seriously concerned about  this information, so i would like to ask if someone could help me understand it better, should i be understanding this properly, i would like to ask if it does exist, for example, some sort of list of suspected or probed hormone emulators.

Just let me thank you for your attention and support.

The nucleus is the point of reference in my spherical coordinates.

Halbach array. is that any good for understanding why opposite spin electrons, that the magnetic fields actually can cancel in macroscopic reality?

Hello dear forum members,

I'm new here and I have registered to ask a question which for some reason is difficult for me to solve on my own as I struggle to wrap my head around it. The problem pertains to electrophilic aromatic substitution reactions. I know how it works, both in theory as well as in practice when it comes to monocyclic arenes like benzene itself and how activating/deactivating ortho/para/meta directors decide over at which C-X the next group will be bonded to (please note that "X" here doesn't stand for halogens but is a placeholder for the position number of the carbon in question).
However, things got complicated for me once I moved on to polycyclic compounds because I have no idea how to "jump" back and forth between neighbouring rings. To make matters worse my textbook only explains Se-Reactions in the context of monocyclic arenes like benzene and phenol.

Let's take for example biphenyl. Assuming the Se-Reaction starts at ring A, how does a chemist ensure that his next reaction takes place at ring B? No matter whether I use activating/deactivating ortho-para-meta directors, the reactions will always take place on ring A, right? What does it take to affect the regioselectivity of the molecule in such a way to "jump" to ring B?

Another example would be the phenanthrene molecule (I have uploaded an image with the numbering system of the (4,5-epoxy)morphinan family). This one is different as ring B is essentially a cycloalkene which responds to E1/E2/E1cb-Reactions as well as Addition-Reactions, so I would assume that simply doing one of these reactions automatically removes/adds functional groups to ring B instead of the neighbouring arenes. But what if I am currently at C-3 of ring A after having substituted the H-atom with an OH-group via Se and want to skip ring B and go directly to ring C (which is also an arene that also responds to Se-Reactions) and add another OH-group at C-6? The OH-group at C-3 would be a strongly activating ortho-para director, so the next reaction will take place at either C-2 or C-4 (ring A). Para isn't possible because C-12 doesn't have any valence electrons left (and even if it had any, there is too much steric hindrance, so a reaction at ortho is much more likely).
I can't imagine that a chemist has to go through the entire ring structure and do a whole range of unnecessary and time-consuming reactions until he reaches his desired C-6 position to manipulate. There must be some kind of standard ruleset that chemists apply in order to address specific rings while leaving others alone. Something that gives us more control over the regioselectivity of the reaction we want to conduct.

Maybe the best way to answer my question would be to tell me how YOU would synthesize the compound 3,6-dihydroxyphenanthrene if you were to start with phenanthrene.

I hope I haven't expressed myself in too complicated a manner and if I did I apologize as english isn't my mother tongue. I have really researched book after book, searched websites and sifted through youtube videos but I haven't found anything that discusses how to affect the regioselectivity of a polycyclic molecule in order to conduct reactions at different rings instead of a single ring. Maybe I'm thinking in overly complicated ways and can't see the forest for the trees anymore. Whatever it is, I need help because this is driving me insane. Thank you.