Table 1. Compilation of Symbols Used in the Article.

$S_X^{\mathit{ex}}$	Unit-area-normalized excitation spectrum of X (D for donor, A for acceptor)
$S_X^{\mathit{em}}$	Unit-area-normalized emission spectrum of X (D for donor, A for acceptor)
SX	Unit-area-normalized excitation-emission spectral signature of X (D for donor, A for acceptor, S for donor-acceptor sensitization): SD = S ex D⊗ S em D, SA = S ex A⊗ S em A, SS = S ex D⊗ S em A, ⊗: Outer product
SDA	Image-stack: Excitation-emission spectrum of FRET sample
KX	Total X (D for donor, A for acceptor) absorption in all excitation wavelengths used: ∫Iex εX(λ)dλ
	(εX(λ) is the extinction coefficient of X at wavelength λ)
rK	The ratio of total acceptor absorption to total donor absorption in all excitation wavelengths used: KA/KD
Cy	Concentration of y (d for free donor, a for free acceptor, da for the paired donor-acceptor)
C t X	Concentration of total X (D for donor, A for acceptor)
QX	Quantum yield of X (D for donor, A for acceptor)
rQ	Quantum yield ratio of acceptor to donor: QA/QD
WX	Weight of component X (D for donor, A for acceptor, S for donor-acceptor sensitization)
E	FRET efficiency of the paired donor-acceptor
Eapp	Apparent FRET efficiency (related to total donor): ECda/C t D
RC	Concentration ratio of acceptor to donor: C t A/C t D