In a PICT state formed by intramolecular charge transfer in an electron donor (D)/acceptor (A) molecule, the D and A subgroups have an overall planar configuration,
with substantial electronic coupling of D and A.
Source:
PAC, 2007, 79, 293
(Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006))
on page 401