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Neptunium Tribromide
Neptunium(III) bromide is a bromide of neptunium, with the chemical formula of NpBr3. Preparation Neptunium(III) bromide can be prepared by reacting neptunium dioxide and aluminium bromide:Georg Brauer (Hrsg.), unter Mitarbeit von Marianne Baudler u. a.: ''Handbuch der Präparativen Anorganischen Chemie.'' 3., umgearbeitete Auflage. Band II, Ferdinand Enke, Stuttgart 1978, ISBN 3-432-87813-3, S. 1268. : Properties Neptunium(III) bromide is a green solid. It can crystallize in two crystal systems: * α-NpBr3 is hexagonal with lattice parameters a = 791.7 pm and c = 438.2 pm. It has the same structure as uranium trichloride. * β-NpBr3 is orthorhombic with lattice parameters a = 411 pm, b = 1265 pm and c = 915 pm. It has the same structure as the bromides from plutonium to californium. Neptunium(III) bromide also has a green hexahydrate, which is monoclinic. Reactions At 425 °C, neptunium(III) bromide bromide can be further brominated by bromine to form nept ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexagonal
In geometry, a hexagon (from Greek , , meaning "six", and , , meaning "corner, angle") is a six-sided polygon. The total of the internal angles of any simple (non-self-intersecting) hexagon is 720°. Regular hexagon A regular hexagon is defined as a hexagon that is both equilateral and equiangular. In other words, a hexagon is said to be regular if the edges are all equal in length, and each of its internal angle is equal to 120°. The Schläfli symbol denotes this polygon as \ . However, the regular hexagon can also be considered as the cutting off the vertices of an equilateral triangle, which can also be denoted as \mathrm\ . A regular hexagon is bicentric, meaning that it is both cyclic (has a circumscribed circle) and tangential (has an inscribed circle). The common length of the sides equals the radius of the circumscribed circle or circumcircle, which equals \tfrac times the apothem (radius of the inscribed circle). Measurement The longest diagonal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
