IMNSHO, no way in so general terms.

If you know the chemical structures, you can do quantum-mechanical calculations of the spectra (a complex task!) and use the absorption spectra as a reference for adjustments of the calculations. But even that cannot warrant the correctness of the calculated emission spectra. Not yet, though the progress in this area is fast and calculated spectra are more and more close to the measured ones...

I agree fully  with the answer of Vladimir.

Your question is too vague and obsolete. Please learn to post a good question concerning your problem.

Please consult a good book about  fluoresence  of molecules. Consult google scholar

On other part launch GOOGLE SCHOLAR  and NOT GOOGLE. and insert your question  via copy and paste and read the hits.

JRG

I searched both google and scholar for the answer. I found nothing and also I read several papers and one book, but also nothing,

Thanks for you 

Please refine your question and give infos about your molecules   (organic? structure and substituents..).  What a kind of QD?

What a kind of a book have you read?

It seems that you are not familiar with web enquiries.

JRG