argon

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argon isolation

first ionization energies of the elements

argon phase diagram

Figure 1: The four stable geometric structures of the seven-atom cluster of argon, in order of increasing energy: (A) A pentagonal bipyramid. (B) A regular octahedron with one face capped by the seventh atom. (C) A regular tetrahedron with three of its faces capped by other atoms. (D) A trigonal bipyramid with two of its faces capped by other atoms; although this has the highest energy of the four structures, it is very close in energy to the tricapped tetrahedron.

Figure 2: The four lowest-energy structures of the 13-atom cluster of argon.

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argon: Facts & Related Content

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Facts

Also Known As	Ar

Photos

argon isolation

first ionization energies of the elements

argon phase diagram

Figure 1: The four stable geometric structures of the seven-atom cluster of argon, in order of increasing energy: (A) A pentagonal bipyramid. (B) A regular octahedron with one face capped by the seventh atom. (C) A regular tetrahedron with three of its faces capped by other atoms. (D) A trigonal bipyramid with two of its faces capped by other atoms; although this has the highest energy of the four structures, it is very close in energy to the tricapped tetrahedron.

Figure 2: The four lowest-energy structures of the 13-atom cluster of argon.

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Topics

argon-40 air chemical element noble gas hydrogen carbon sodium nitrogen sulfur phosphorus boron iodine fluorine zinc

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William Ramsay

Sir William Ramsay

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Lord Rayleigh, engraving by R. Cottot.

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