Variables and Constants
From CleanEnergyWIKI
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Common
Symbol | Meaning |
---|---|
c | speed of light (c = 299,792,458 m/s approx 3 x 10^{6}m/s) |
ν | frequency |
h | planck's constant (h = 6.62606896x 10^{-34} J s = 4.135667 x 10^{-15}eV s) |
λ | wavelength (visible spectrum is 400-700nm) |
Absorption and Emission
Symbol | Meaning |
---|---|
ε | extinction coefficient of a molecule |
Φ | quantum yield |
Ψ | wave function |
EO Properties
Symbol | Meaning |
---|---|
μ | dipole moment (mu) measured in debyes |
α | linear polarizability (alpha) |
β | molecular first hyperpolarizability (microscopic) (beta) |
γ | molecular second hyperpolarizability (microscopic) (gamma) |
cos^{3}θ | order parameter |
δ | Two-photon cross section measured in Goppert-Mayer units (GM), with 1 GM=1×10^{-50} cm^{4} s molecules^{−1} photon^{−1} >100gm is high.) |
r | Pockels coefficient or Linear Electo-optic Coefficient Pockels Effect r~ 10^{-12} – 1^{—10} m/V |
r_{33} | Electro-optic coefficient (chi 33)(FM= 1000 pm/V) |
χ^{2} | second-order nonlinear susceptibility (first order hyperpolarizability) (macroscopic) |
χ^{3} | third-order nonlinear susceptibility (second order hyperpolarizability) (macroscopic) (alpha)(FM= 6-7 x 10^{-21}(m/V)^{2}) |
ε | dielectric constant or relative static permittivity |
M | Transition dipole moment (measured in debyes) |
N | Number Density parameter |
φ_{fl} | Fluorescence Quantum Yield a ratio of photons absorbed over photons emitted |
σ | conductivity (measured in S (Siemens)/cm |
t | the electronic coupling, transfer integral or resonance integral |
v_{π} | half-wave driving voltage |
Devices
Symbol | Meaning |
---|---|
α | material loss in dB/cm |
d | electrode separation |
Γ | optical electrical overlap |
λ | reorganization energy |
μ | charge mobility in cm^{2} / V s- a mobility >1 is considered good |
see also Wikipedia Greek Letters in Science