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Chemistry Forums for Students => Inorganic Chemistry Forum => Topic started by: srya2000 on March 04, 2013, 05:36:37 PM

Title: Reading IR Spectrum
Post by: srya2000 on March 04, 2013, 05:36:37 PM

Hello i did a lab where i made up Cu(NH₃)SO₄ H₂O and obtained a IR spectrum

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Sorry about the bad images. I know that SO₄ (v₃) is around 1104/cm and NH₃ (δd) is around 1628/cm but i have no idea what that big dip in at 3201/cm is. I have to figure out if this is a Sulfato ligand binding as unidentate complex, bidenate complex, or bridged bidentate complex. I have watch a bunch of youtube videos and lab reports and cant understand how to properly read this. I read my text book as well but still dont get it. I was also a bit confused because i thought the NH₃ would be double bonded to the SO₄ since its in the double bond range but thats not an option. Please help me out if you can and directed me somewhere else if you cant. Thanks.

Title: Re: Reading IR Spectrum
Post by: Corribus on March 05, 2013, 09:41:23 AM

Resolution is bad, but usually any broad peak in that region of the spectrum can be assumed to be water or something with a hydrogen-bonded OH group.  Given your sample has water in it, this seems to be almost certainly what it is.