FCSXpert Solutions: Fluorescence Correlation Spectroscopy Simplified!.
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Parameter Definitions

Number of particles
Number of dye molecules
e-2 beam radius in xy plane
e-2 beam radius along z axis
wz/w
fraction of intersystem crossing
fraction of a diffusing component
diffusion coefficient
flow velocity
w2/4D
w/v

    FCS Classroom

    List of FCS Equations for Various Physical Processes

    The table below gives the mathematical forms of the correlation functions for several common physical processes. See the table at the bottom-left for parameter definitions:

    Note: For simplicity's sake, we have replaced 'Δt' (used in What is FCS? and Mathematics of Autocorrelation sections) with 't'.

    Process G(t)
    1D Diffusion
    2D Diffusion
    3D Diffusion
    Multicomponent 3D Diffusion
    3D Diffusion with Directed Flow
    Chemical kinetics where binding produces a signal otherwise not present (e.g. FRET)
    3D Diffusion with Intersystem Crossing
    3D Diffusion with System Correction

    Note: For simplicity's sake, we have replaced 'Δt' (used in What is FCS? and Mathematics of Autocorrelation sections) with 't'.