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    can anyone give me some explanation about how we assign absorption bands for phenyl ring in UV-vis spectroscopy?also confusing about their range and ???* transitions.hoping.

    warm regards
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    or we couln't assign phneyl rings,only assign pi to pi* but how their range?anybody help pls.
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    Generally you would see Pi to Pi* bands on a phenyl ring in the far UV region around 200-300nm I believe (if my memory of organic serves me well).
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    (Original post by joshed)
    Generally you would see Pi to Pi* bands on a phenyl ring in the far UV region around 200-300nm I believe (if my memory of organic serves me well).
    oohh,how about their molar absorptivity values joshed?am i right it is above 10 000?i have run my compounds which have phenyl ring in dichloromethane solvent. thus. i'll assume cutoff of dichloromethane overlapping with phenyl ring if you said pi to pi* bands at around 200-300 nm.am i right?
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    (Original post by hidayah)
    oohh,how about their molar absorptivity values joshed?am i right it is above 10 000?i have run my compounds which have phenyl ring in dichloromethane solvent. thus. i'll assume cutoff of dichloromethane overlapping with phenyl ring if you said pi to pi* bands at around 200-300 nm.am i right?
    I couldn't possible comment for a particular compound but a generalisation. Genereally you would see a molar absorbance above 10000 because Pi to Pi* is formally aloud transition and I would expect to see it around the 200-300 nm region.
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    (Original post by joshed)
    I couldn't possible comment for a particular compound but a generalisation. Genereally you would see a molar absorbance above 10000 because Pi to Pi* is formally aloud transition and I would expect to see it around the 200-300 nm region.
    Alright really Thanks joshed for the info their range at least i got ranging and transition which coould be.
    i'm happy atleast i have the answer that.
    Many thanks
 
 
 
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