Template talk:Uranium compounds

Uranium diboride

Why is UB₂ listed under uranium(II) compounds? Shouldn't it be one of:

• uranium(-VI), corresponding to [B⁺³]₂U^-6 (but electronegativity!);
• uranium(X), corresponding to U⁺¹⁰[B^-5]₂ (can relativity really justify donating >6 valence electrons?);
• uranium(VIII), corresponding to U⁺⁸(B^-4–B^-4) (same);
• uranium(VI), corresponding to U⁺⁶(B^-3=B^-3) (plausible, albeit high oxidation for a boron alloy); or
• uranium(IV), corresponding to U⁺⁴(B^-2≡B^-2) (my money's on this one)?

Uranium(II) only makes sense if the boron atoms are connected in a quadruple bond, and there is no evidence of first-row atoms making more than three bonds.

Bernanke's Crossbow (talk) 22:01, 17 July 2023 (UTC)

In uranium diboride, the boron atoms are in sheets, so not simple diatomic ions. I'm guessing U(II) is from the fact that UB₂ is isostructural with MgB₂ which involves Mg(II).

However, most sources agree that uranium does not form compounds in the +2 oxidation state, and the corresponding neptunium compound (and possibly plutonium compound) has a +4 oxidation state.

I propose moving it to U(IV).

UnbihexiumFan (talk) 17:51, 13 August 2025 (UTC)