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Submetallic minerals have similar lustre to metal, but are duller and less reflective. A submetallic lustre often occurs in near-opaque minerals with very high refractive indices, [ 2 ] such as sphalerite , cinnabar , anthracite , and cuprite .
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.
This is a list of sources of light, the visible part of the electromagnetic spectrum.Light sources produce photons from another energy source, such as heat, chemical reactions, or conversion of mass or a different frequency of electromagnetic energy, and include light bulbs and stars like the Sun. Reflectors (such as the moon, cat's eyes, and mirrors) do not actually produce the light that ...
The electronic properties of ordered, crystalline solids are determined by the distribution of the electronic states with respect to energy and momentum—the electronic band structure of the solid. Theoretical models of photoemission from solids show that this distribution is, for the most part, preserved in the photoelectric effect.
A white light source—emitting light of multiple wavelengths—is focused on a sample (the pairs of complementary colors are indicated by the yellow dotted lines). Upon striking the sample, photons that match the energy gap of the molecules present (green light in this example) are absorbed , exciting the molecules.
Solid-state lighting (SSL) is a type of lighting that uses semiconductor light-emitting diodes (LEDs), organic light-emitting diodes (OLED), or polymer light-emitting diodes (PLED) as sources of illumination rather than electrical filaments, plasma (used in arc lamps such as fluorescent lamps), or gas.
The solid form (density 0.0763 g/cm 3) has a cubic crystalline structure and is soft and easily crushed. Oxygen is an insulator in all of its forms. It has a high ionisation energy (1313.9 kJ/mol), moderately high electron affinity (141 kJ/mol), and high electronegativity (3.44). Oxygen is a strong oxidising agent (O 2 + 4e → 2H 2 O = 1.23 V ...
Luminous energy is related to radiant energy by the expression = / ¯ (). Here λ {\displaystyle \lambda } is the wavelength of light, and y ¯ ( λ ) {\displaystyle {\overline {y}}(\lambda )} is the luminous efficiency function , which represents the eye's sensitivity to different wavelengths of light.