Components ωAA and ωBB represent the probability of an exciton residing entirely on a single respective monomer (A or B) (Frenkel exciton), while ωAB and ωBA represent the probability of an electron being donated from one monomer to the other (CT exciton). Elements of a CT matrix shown in Equation are obtained from the one-particle transition density matrix in the atomic orbital (AO) basis ) $ [&' ! ] , given as 83 (Eq. 4.2):