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Antozonite
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Stinky rocks hide Earths only haven for natural fluorine

Chemists have proved that a smelly rock is the only known place on Earth where fluorine exists in its elemental form, F2.
The rock is antozonite, a calcium fluoride (fluorite) mineral that is dark violet or even black in colour, also known as fetid fluorite or stinkspar. Needless to say, this rock stinks. The pungent smell is given off when antozonite is crushed, and chemists and mineralogists have argued over the origin of the stench since the early nineteenth century.

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RE: Fluorine
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After 74 years of effort by other chemists, on 26 June 1886, a French chemist Ferdinand Frederick Henri Moissan(1852 - 1907) reported the isolation of elemental fluorine.
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Title: Molecular fluorine chemistry in the early Universe
Authors: Denis Puy, Victor Dubrovich, Anton Lipovka, Dahbia Talbi, Patrick Vonlanthen

Some models of Big Bang nucleosynthesis suggest that very high baryon density regions were formed in the early Universe, and generated the production of heavy elements other than lithium such as fluorine F. We present a comprehensive chemistry of fluorine in the post-recombination epoch. Calculation of F, F- and HF abundances, as a function of redshift z, are carried out. The main result is that the chemical conditions in the early Universe can lead to the formation of HF. The final abundance of the diatomic molecule HF is predicted to be close to 3.75 10(-17) when the initial abundance of neutral fluorine F is 10(-15). These results indicate that molecules of fluorine HF were already present during the dark age. This could have implications on the evolution of proto-objects and on the anisotropies of cosmic microwave background radiation. Hydride of fluorine HF may affect enhancement of the emission line intensity from the proto-objects and could produce spectral-spatial fluctuations.

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Title: Discovery of Fluorine in Cool Extreme Helium Stars
Authors: Gajendra Pandey (Indian Institute of Astrophysics, Bangalore, India)

Neutral fluorine (F I) lines are identified in the optical spectra of cool EHe stars. These are the first identification of F I lines in a star's spectrum, and provide the first measurement of fluorine abundances in EHe stars. The results show that fluorine is overabundant in EHe stars. The overabundance of fluorine provides evidence for the synthesis of fluorine in these stars, that is discussed in the light of asymptotic giant branch (AGB) evolution, and the expectation from accretion of an He white dwarf by a C-O white dwarf.

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