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Phosphorus pentabromide is a reactive, yellow solid of formula P Br 5, which has the structure [PBr 4] + Br − (tetrabromophosphonium bromide) in the solid state but in the vapor phase is completely dissociated to PBr 3 and Br 2.
formula system space group unit cell Å volume density comment ref Ca 2 PBr : cubic I 4 3d: a=5.96 Z=2 red brown [1]Ca 2 PBr : hexagonal R 3 m: a=4.23 c=20.9 Z=3 [1]Cu 12 P 20 Br 10: triclinic
In three-dimensional symmetry point groups, the transformations preserving a polyhedron's symmetry include the rotation around the line passing through the base center, known as the axis of symmetry, and the reflection relative to perpendicular planes passing through the bisector of a base, which is known as the pyramidal symmetry of order .
Thus, phosphorescence literally means "having a tendency to bear light". It was first recorded in 1766. [7] The term phosphor had been used since the Middle Ages to describe minerals that glowed in the dark. One of the most famous, but not the first, was Bolognian phosphor. Around 1604, Vincenzo Casciarolo discovered a "lapis solaris" near ...
The zero-phonon line and the phonon sideband jointly constitute the line shape of individual light absorbing and emitting molecules (chromophores) embedded into a transparent solid matrix. When the host matrix contains many chromophores, each will contribute a zero- phonon line and a phonon sideband to the absorption and emission spectra .
Solid light, or hard light, is a hypothetical material consisting of light in a solidified state. It has been theorized that solid light could exist. [ 1 ] [ 2 ] Some experiments claim to have created solid photonic matter or molecules by inducing strong interaction between photons.
Light scattering in liquids and solids depends on the wavelength of the light being scattered. Limits to spatial scales of visibility (using white light) therefore arise, depending on the frequency of the light wave and the physical dimension (or spatial scale) of the scattering center. Visible light has a wavelength scale on the order of 0.5 μm.
Caubère defines superbases as "bases resulting from a mixing of two (or more) bases leading to new basic species possessing inherent new properties. The term superbase does not mean a base is thermodynamically and/or kinetically stronger than another, instead it means that a basic reagent is created by combining the characteristics of several ...