ATRA	atom transfer radical addition
CT	charge transfer
DCM	dichloromethane
DFT	density functional theory
EDA	electron donor–acceptor
HOMO	highest occupied molecular orbital
IC	internal conversion
ISC	intersystem crossing
KS	Kohn–Sham
LED	light-emitting diode
LUMO	lowest unoccupied molecular orbital
MRCI	multi-reference configuration interaction
MRSOCI	multi-reference spin–orbit configuration interaction
PES	potential energy surface
QDPT	quasi-degenerate perturbation theory
SOC	spin–orbit coupling
SOCME	spin–orbit coupling matrix element
SOMO	singly occupied molecular orbital
TDDFT	time-dependent density functional theory
TDA	Tamm–Dancoff approximation