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14-401: Zinc sulfide (or zinc sulphide ) is an inorganic compound with the chemical formula of ZnS. This is the main form of zinc found in nature, where it mainly occurs as the mineral sphalerite . Although this mineral is usually black because of various impurities, the pure material is white, and it is widely used as a pigment. In its dense synthetic form, zinc sulfide can be transparent , and it

28-436: A scintillation detector, because it emits light upon excitation by x-rays or electron beam , making it useful for X-ray screens and cathode-ray tubes. This property made zinc sulfide useful in the dials of radium watches. Zinc sulfide is usually produced from waste materials from other applications. Typical sources include smelter, slag, and pickle liquors. As an example, the synthesis of ammonia from methane requires

42-447: A priori removal of hydrogen sulfide impurities in the natural gas, for which zinc oxide is used. This scavenging produces zinc sulfide: Crude zinc sulfide can be produced by igniting a mixture of zinc and sulfur . More conventionally, ZnS is prepared by treating a mildly acidic solution of Zn salts with H 2 S : This reaction is the basis of a gravimetric analysis for zinc. Inorganic compound An inorganic compound

56-518: A water-clear form known as Cleartran (trademark). Early commercial forms were marketed as Irtran-2 but this designation is now obsolete. Zinc sulfide is a common pigment , sometimes called sachtolith. When combined with barium sulfate, zinc sulfide forms lithopone . Fine ZnS powder is an efficient photocatalyst , which produces hydrogen gas from water upon illumination. Sulfur vacancies can be introduced in ZnS during its synthesis; this gradually turns

70-484: Is also used as an infrared optical material, transmitting from visible wavelengths to just over 12 micrometers . It can be used planar as an optical window or shaped into a lens . It is made as microcrystalline sheets by the synthesis from hydrogen sulfide gas and zinc vapour, and this is sold as FLIR -grade (Forward Looking Infrared), where the zinc sulfide is in a milky-yellow, opaque form. This material when hot isostatically pressed (HIPed) can be converted to

84-408: Is bright blue, with maximum at 450 nanometers . Using manganese yields an orange-red color at around 590 nanometers. Copper gives a longer glow, and it has the familiar greenish glow-in-the-dark. Copper-doped zinc sulfide ("ZnS plus Cu") is used also in electroluminescent panels. It also exhibits phosphorescence due to impurities on illumination with blue or ultraviolet light. Zinc sulfide

98-616: Is often cited as the starting point of modern organic chemistry . In Wöhler's era, there was widespread belief that organic compounds were characterized by a vital spirit . In the absence of vitalism, the distinction between inorganic and organic chemistry is merely semantic. Luminescence Luminescence is a spontaneous emission of radiation from an electronically or vibrationally excited species not in thermal equilibrium with its environment.   A luminescent object emits cold light in contrast to incandescence , where an object only emits light after heating. Generally,

112-590: Is typically a chemical compound that lacks carbon–hydrogen bonds ⁠ ‍ — ‍ that is, a compound that is not an organic compound . The study of inorganic compounds is a subfield of chemistry known as inorganic chemistry . Inorganic compounds comprise most of the Earth's crust , although the compositions of the deep mantle remain active areas of investigation. All allotropes (structurally different pure forms of an element) and some simple carbon compounds are often considered inorganic. Examples include

126-421: Is used as a window for visible optics and infrared optics. ZnS exists in two main crystalline forms . This dualism is an example of polymorphism . In each form, the coordination geometry at Zn and S is tetrahedral. The more stable cubic form is known also as zinc blende or sphalerite . The hexagonal form is known as the mineral wurtzite , although it also can be produced synthetically. The transition from

140-541: The allotropes of carbon ( graphite , diamond , buckminsterfullerene , graphene , etc.), carbon monoxide CO , carbon dioxide CO 2 , carbides , and salts of inorganic anions such as carbonates , cyanides , cyanates , thiocyanates , isothiocyanates , etc. Many of these are normal parts of mostly organic systems, including organisms ; describing a chemical as inorganic does not necessarily mean that it cannot occur within living things. Friedrich Wöhler 's conversion of ammonium cyanate into urea in 1828

154-695: The emission of light is due to the movement of electrons between different energy levels within an atom after excitation by external factors. However, the exact mechanism of light emission in vibrationally excited species is unknown. The dials, hands, scales, and signs of aviation and navigational instruments and markings are often coated with luminescent materials in a process known as luminising . Luminescence occurs in some minerals when they are exposed to low-powered sources of ultraviolet or infrared electromagnetic radiation (for example, portable UV lamps ) at atmospheric pressure and atmospheric temperatures. This property of these minerals can be used during

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168-491: The hexagonal form has a band gap of about 3.91 electron volts. ZnS can be doped as either an n-type semiconductor or a p-type semiconductor . The phosphorescence of ZnS was first reported by the French chemist Théodore Sidot in 1866. His findings were presented by A. E. Becquerel , who was renowned for the research on luminescence . ZnS was used by Ernest Rutherford and others in the early years of nuclear physics as

182-417: The sphalerite form to the wurtzite form occurs at around 1020  °C . Zinc sulfide, with addition of a few ppm of a suitable activator , exhibits strong phosphorescence . The phenomenon was described by Nikola Tesla in 1893, and is currently used in many applications, from cathode-ray tubes through X-ray screens to glow in the dark products. When silver is used as activator, the resulting color

196-435: The white-yellowish ZnS into a brown powder, and boosts the photocatalytic activity through enhanced light absorption. Both sphalerite and wurtzite are intrinsic, wide- bandgap semiconductors . These are prototypical II-VI semiconductors , and they adopt structures related to many of the other semiconductors, such as gallium arsenide . The cubic form of ZnS has a band gap of about 3.54 electron volts at 300 kelvins , but

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