For further info, the link mentions this article. If I got it correctly:
Higher pressure compresses the orbitals of the sodium atoms, making them more cluttered together. As a result, the outer electrons - that “should” be in the 3s orbital, surrounding the nucleus like a bubble - are repelled to more energetic orbitals, like 3p and 3d. Those orbitals have “lobes” reaching far from the nucleus, so further away from the other electrons.
But since the sodium atoms are not isolated, and all those sodium atoms are doing this at the same time, the 3p and 3d orbitals from multiple atoms overlap. Orbitals overlapping form a chemical bond. And, since it’s damn hard to remove electrons from those bonds to send them elsewhere, electrical conductivity goes down. Sodium becomes first a semiconductor, then an isolating material.
So it’s a lot like your usual macromolecules (like, silicon dioxide or diamond), except that those bonds are shared by multiple atoms, not just two. And I don’t think that it’s a coincidence that all three are transparent, given that those electrons “stuck” in specific molecular orbitals suck major balls at absorbing photons and releasing them back.
Personal predictions:
high-pressure sodium should be bloody hard, and not malleable at all. Kind of funny given that normal pressure sodium is really soft.
other s-block metals will behave similarly under high pressure. If exceptions exist, they’ll be the largest ones (in this order: radium, francium, barium, caesium).
aluminium and gallium might behave similarly, but you’ll need a lot more pressure to pull it out. (Note: this is completely unrelated to a certain oxygen/nitrogen/aluminium ceramic that was developed recently.)
For further info, the link mentions this article. If I got it correctly:
Higher pressure compresses the orbitals of the sodium atoms, making them more cluttered together. As a result, the outer electrons - that “should” be in the 3s orbital, surrounding the nucleus like a bubble - are repelled to more energetic orbitals, like 3p and 3d. Those orbitals have “lobes” reaching far from the nucleus, so further away from the other electrons.
But since the sodium atoms are not isolated, and all those sodium atoms are doing this at the same time, the 3p and 3d orbitals from multiple atoms overlap. Orbitals overlapping form a chemical bond. And, since it’s damn hard to remove electrons from those bonds to send them elsewhere, electrical conductivity goes down. Sodium becomes first a semiconductor, then an isolating material.
So it’s a lot like your usual macromolecules (like, silicon dioxide or diamond), except that those bonds are shared by multiple atoms, not just two. And I don’t think that it’s a coincidence that all three are transparent, given that those electrons “stuck” in specific molecular orbitals suck major balls at absorbing photons and releasing them back.
Personal predictions: