my intuition is that the liaison aren't covalent as you learnt it and as the line would let you infer but coordinate covalent (if my translation is correct). This means that the 2 electrons involved in the liaison come from the lone pair.
My assumption is that the carbon lone pair will be stronger than the one from the nitrogen as there is a formal - charge on the carbon.
This is important because the crystal field will depend on the strength of the ligand, which will be related to the "quality of the bond".
Because Fe2+ has one more electron, I would have assumed that it is more favourable to have a large cristal field splitting, high spin configuration. I suspect the entire thing is more complicated as Fe3+ is not just surrounded by 6N and therefore there will be even more cristal field splitting.
I don't have a clear explanation on the specificity of Prussian blue so a lot of it is hand-wavy assumptions from basic cristal field theory that may not even be (directly) applicable here
CCochard
npub1pe…gqu4z
2025-09-30 20:34:40 UTC
in reply to nevent1q…yv4z
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wss://relay.momostr.pinkPublished at
2025-09-30 20:34:40 UTCEvent JSON
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"content": "my intuition is that the liaison aren't covalent as you learnt it and as the line would let you infer but coordinate covalent (if my translation is correct). This means that the 2 electrons involved in the liaison come from the lone pair.\nMy assumption is that the carbon lone pair will be stronger than the one from the nitrogen as there is a formal - charge on the carbon. \nThis is important because the crystal field will depend on the strength of the ligand, which will be related to the \"quality of the bond\".\n\nBecause Fe2+ has one more electron, I would have assumed that it is more favourable to have a large cristal field splitting, high spin configuration. I suspect the entire thing is more complicated as Fe3+ is not just surrounded by 6N and therefore there will be even more cristal field splitting. \n\nI don't have a clear explanation on the specificity of Prussian blue so a lot of it is hand-wavy assumptions from basic cristal field theory that may not even be (directly) applicable here",
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