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#1 2021-02-22 08:17:29
- saeed_E
- Member
- Registered: 2019-12-21
- Posts: 244
Blue-shift instead of expected red-shift in XB-bonded complexes
Dear Tian,
In some cases of XB-bonded complexes such as R-F...Y or R-Cl...Y (R: highly electron-withdrawing group, Y: Lewis base), after formation of complex the R-F (R-Cl) distance is contracted instead of an expected elongation! In other words, while we expect a red-shift happens for the R-F stretching frequency, a blue-shift is observed instead; that is, R-F distance in R-F...Y complex is shorter than the respective value in the isolated R-F.
Could you please let me know your valuable rationalization regarding such an unexpected contraction happened in R-F distance?
Sincerely,
Saeed
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#2 2021-02-22 12:14:43
Re: Blue-shift instead of expected red-shift in XB-bonded complexes
I don't have a clear answer. Please try to google something like "blue-shift halogen-bond" to see if there are existing relevant studies.
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#3 2021-02-22 15:06:45
- saeed_E
- Member
- Registered: 2019-12-21
- Posts: 244
Re: Blue-shift instead of expected red-shift in XB-bonded complexes
Dear Tian,
Thank you very much for your valuable guidance.
Sincerely,
Saeed
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