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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: elt2112 on May 11, 2015, 01:35:22 PM

Title: Lanthanide coordination
Post by: elt2112 on May 11, 2015, 01:35:22 PM

Explain why lanthanum is 11 coordinate in LaF₃, whilst lutetium is 9 coordinate in LuF₃, but 6 coordinate in LuCl₃.

So I'm guessing the fact that lutetium 3+ has a significantly smaller ionic radius would account for the fact it has a smaller coordination number. But what reason is there for the difference between LuF₃ and LuCl₃? Would it be because chlorine is larger than fluorine?

Title: Re: Lanthanide coordination
Post by: mjc123 on May 11, 2015, 06:08:22 PM

Yes