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Author Topic: Colors of TM complexes  (Read 727 times)

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luketapis

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Colors of TM complexes
« on: December 05, 2012, 11:17:37 PM »

Hi I have a question:
The two complexes [NI(OH2)2]2+ and [Ni(NH3)]2+
are both colored. One is green, the other is blue. Which is which?

Ok, so both complexes are octahedral and d8
[NI(OH2)2]2+ is high spin and weak field.
[Ni(NH3)]2+ is strong field ligand = low spin.
How from this information distinguish colors?
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sjb

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Re: Colors of TM complexes
« Reply #1 on: December 05, 2012, 11:25:58 PM »

Hi I have a question:
The two complexes [NI(OH2)2]2+ and [Ni(NH3)]2+
are both colored. One is green, the other is blue. Which is which?

Ok, so both complexes are octahedral and d8
[NI(OH2)2]2+ is high spin and weak field.
[Ni(NH3)]2+ is strong field ligand = low spin.
How from this information distinguish colors?

What is the cause of the colour?
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luketapis

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Re: Colors of TM complexes
« Reply #2 on: December 06, 2012, 12:04:29 AM »

absorption of light with a particular wavelength
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sjb

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Re: Colors of TM complexes
« Reply #3 on: December 06, 2012, 01:27:49 AM »

absorption of light with a particular wavelength

And on a physical level, what is happening?
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luketapis

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Re: Colors of TM complexes
« Reply #4 on: December 06, 2012, 11:59:52 AM »

d-d transition
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sjb

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Re: Colors of TM complexes
« Reply #5 on: December 08, 2012, 10:03:09 PM »

Sorry, missed the reply. That sounds good (possibly d  :rarrow: d*, if I remember right, but it's been a while). So, if the energy gap between these levels is small, what does that mean for the light absorbed in the transition?
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luketapis

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Re: Colors of TM complexes
« Reply #6 on: December 09, 2012, 12:40:18 AM »

I don't know
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sjb

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Re: Colors of TM complexes
« Reply #7 on: December 10, 2012, 11:18:56 AM »

Do you know any relationship between frequency of light and energy?
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