Does anyone know of a database of T1/T2 relaxation values for various functional groups in 1H NMR?
I don't know exactly which data base it could be but you could check or ask from the following site:http://www.wnmrc.nl/Introduction.htm
Here is a database I came across.
Spectral Database for Organic Compounds SDBS:
Also, here is a link for a page containing other NMR databases.