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:
“If rightly made, a boat would be a sort of amphibious animal, a creature of two elements, related by one half its structure to some swift and shapely fish, and by the other to some strong-winged and graceful bird.”
—Henry David Thoreau (18171862)
“Vashtar: So its finished. A structure to house one man and the greatest treasure of all time.
Senta: And a structure that will last for all time.
Vashtar: Only history will tell that.
Senta: Sire, will he not be remembered?
Vashtar: Yes, hell be remembered. The pyramidll keep his memory alive. In that he built better than he knew.”
—William Faulkner (18971962)
“Im a Sunday School teacher, and Ive 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 yourselfa 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, dont permit us to achieve perfection.”
—Jimmy Carter (James Earl Carter, Jr.)