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The Sellmeier equation is an empirical relationship between refractive index and wavelength for a particular transparent medium. The equation is used to determine the dispersion of light in the medium. It was first proposed in 1872 by Wolfgang Sellmeier and was a development of the work of Augustin Cauchy on Cauchy's equation for modelling ...
In optics, Cauchy's transmission equation is an empirical relationship between the refractive index and wavelength of light for a particular transparent material. It is named for the mathematician Augustin-Louis Cauchy , who originally defined it in 1830 in his article "The refraction and reflection of light".
Std enthalpy change of formation, Δ f H o solid-1675.7 kJ/mol Standard molar entropy, S o solid: 50.92 J/(mol K) Heat capacity, c p: 89.7248 J/(mol K) Liquid properties Std enthalpy change of formation, Δ f H o liquid-1620.57 kJ/mol Standard molar entropy, S o liquid: 67.24 J/(mol K) Heat capacity, c p: 192.5 J/(mol K) Gas properties Std ...
Wolfgang Sellmeier was a German theoretical physicist who made major contributions to the understanding of the interactions between light and matter. [1] In 1872 he published his seminal work Ueber die durch die Aetherschwingungen erregten Mitschwingungen der Körpertheilchen und deren Rückwirkung auf die ersteren, besonders zur Erklärung der ...
A. R. Forouhi and I. Bloomer deduced dispersion equations for the refractive index, n, and extinction coefficient, k, which were published in 1986 [1] and 1988. [2] The 1986 publication relates to amorphous materials, while the 1988 publication relates to crystalline.
The extremely low coefficient of thermal expansion, about 5.5 × 10 −7 /K (20–320 °C), accounts for its remarkable ability to undergo large, rapid temperature changes without cracking (see thermal shock). Phosphorescence in fused quartz from an extremely intense pulse of UV light in a flashtube, centered at 170 nm
The standard state of a material (pure substance, mixture or solution) is a reference point used to calculate its properties under different conditions.A degree sign (°) or a superscript Plimsoll symbol (⦵) is used to designate a thermodynamic quantity in the standard state, such as change in enthalpy (ΔH°), change in entropy (ΔS°), or change in Gibbs free energy (ΔG°).
2, and coke (impure carbon) to produce P 4. The chemical equation for this process when starting with fluoroapatite, a common phosphate mineral, is: 4 Ca 5 (PO 4) 3 F + 18 SiO 2 + 30 C → 3 P 4 + 30 CO + 18 CaSiO 3 + 2 CaF 2. Of historic interest is the Leblanc process. A key step in this process is the reduction of sodium sulfate with coal: [3]