Structure
Its structure adopts the rhenium trioxide motif, featuring distorted AlF6 octahedra. Each fluoride is connected to two Al centers. Because of it is a 3-dimensional polymer, AlF3 has a higher melting point. In contrast, the other trihalides of aluminium, AlCl3, AlBr3, and AlI3, which are either molecular or 1-dimensional polymers, have low melting points and evaporate readily to give dimers. In the gas phase, at ca. 1000 °C, aluminium fluoride exists as trigonal molecules of D3h symmetry. The Al-F bond lengths of this gaseous molecule are 163 pm.
Read more about this topic: Aluminium Fluoride
Famous quotes containing the word structure:
“Man is more disposed to domination than freedom; and a structure of dominion not only gladdens the eye of the master who rears and protects it, but even its servants are uplifted by the thought that they are members of a whole, which rises high above the life and strength of single generations.”
—Karl Wilhelm Von Humboldt (1767–1835)
“Slumism is the pent-up anger of people living on the outside of affluence. Slumism is decay of structure and deterioration of the human spirit. Slumism is a virus which spreads through the body politic. As other “isms,” it breeds disorder and demagoguery and hate.”
—Hubert H. Humphrey (1911–1978)
“I’m a Sunday School teacher, and I’ve always known that the structure of law is founded on the Christian ethic that you shall love the Lord your God and your neighbor as yourself—a very high and perfect standard. We all know the fallibility of man, and the contentions in society, as described by Reinhold Niebuhr and many others, don’t permit us to achieve perfection.”
—Jimmy Carter (James Earl Carter, Jr.)