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Group of chemical elements
The chalcogens (/ˈkælkədʒənz/, KAL-kə-jənz) are the chemical elements in group 16 of the periodic table. This group is also known as the oxygen family
Chalcogen
Chemical compound with hydrogen and chalcogen atoms
Hydrogen chalcogenides (also chalcogen hydrides or hydrogen chalcides) are binary compounds of hydrogen with chalcogen atoms (elements of group 16: oxygen
Hydrogen_chalcogenide
Net attractive interaction involving one of the chalcogen elements
In chemistry, a chalcogen bond (ChB) is an attractive interaction in the family of σ-hole interactions, along with halogen bonds. Electrostatic, charge-transfer
Chalcogen_bond
Class of chemical compounds
one chalcogen anion and at least one more electropositive element. Although all group 16 elements of the periodic table are defined as chalcogens, the
Chalcogenide
Chemical element with atomic number 27 (Co)
Cobalt is a chemical element; it has symbol Co and atomic number 27. As with nickel, cobalt is found in the Earth's crust only in a chemically combined
Cobalt
Chemical element with atomic number 52 (Te)
is chemically related to selenium and sulfur, all three of which are chalcogens. It is occasionally found in its native form as elemental crystals. Tellurium
Tellurium
Chemical element with atomic number 116 (Lv)
in group 16 as the heaviest chalcogen, but it has not been confirmed to behave as the heavier homologue to the chalcogen polonium. Livermorium is calculated
Livermorium
Geochemical classification
(rock-loving), siderophile (iron-loving), chalcophile (sulfide ore-loving or chalcogen-loving), and atmophile (gas-loving) or volatile (the element, or a compound
Goldschmidt_classification
Index of chemical compounds with the same name
Carbon dichalcogenides are chemical compounds of carbon and chalcogen elements. They have the general chemical formula CZ2, where Z = O, S, Se, Te. This
Carbon_dichalcogenide
Chemical element with atomic number 34 (Se)
(SeOCl2)—have been used as specialty solvents. Analogous to the behavior of other chalcogens, selenium forms hydrogen selenide, H2Se. It is a strongly odiferous, toxic
Selenium
Chemical element with atomic number 84 (Po)
sometimes classified as a metalloid) with no stable isotopes, polonium is a chalcogen and chemically similar to selenium and tellurium, though its metallic
Polonium
group 14 element, known as a tetrel, and a group 16 element, known as a chalcogen. The group 14 elements are carbon, silicon, germanium, tin, lead and flerovium
Chalcogenidotetrelate
Chemical element with atomic number 79 (Au)
Wickleder, Mathias S. (2007). Devillanova, Francesco A. (ed.). Handbook of chalcogen chemistry: new perspectives in sulfur, selenium and tellurium. Royal Society
Gold
Tabular arrangement of the chemical elements
alkaline earth metals are among the most electropositive elements, while the chalcogens, halogens, and noble gases are among the most electronegative ones. Electronegativity
Periodic_table
Net attractive interaction involving one of the pnictogen elements
may be in the same or another molecule. Closely related to halogen and chalcogen bonding, pnictogen bonds are a form of non-covalent interaction which
Pnictogen_bond
Family of double sulfate salts of aluminium
trivalent metal ion like chromiumIII, or sulfur is replaced by another chalcogen like selenium. The most common of these analogs is chrome alum KCr(SO4)2·12H2O
Alum
Calcium titanium oxide mineral
perovskite structure, which has a general chemical formula A2+B4+(X2−)3 for chalcogen (group 16) perovskites, or A1+B2+(X1−)3 for the halogen (group 17) perovskites
Perovskite
Chemical compound
includes multi-electron addition and insertion processes (for example, chalcogen insertion), as well as small-molecule transformations that are uncommon
Diboryne
Class of boron heterocyclic compounds
the identity and structure of the chalcogen substrates. The typical DBA dianion can cleave different chalcogen-chalcogen bonds to furnish the syn-diadduct
Diboraanthracene
Process of converting organic compounds into nitroso derivatives
Nitrosation and nitrosylation are two names for the process of converting organic compounds or metal complexes into nitroso derivatives, i.e., compounds
Nitrosation_and_nitrosylation
Chemical compound
Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C6H5)3 and often abbreviated to PPh3 or Ph3P
Triphenylphosphine
Italian chemist
particular focus on self-assembly processes driven by halogen bonds, chalcogen bonds, and pnictogen bonds. His results on the attractive non-covalent
Giuseppe_Resnati
Amino acids not naturally encoded in the genome
selenohomocysteine, selenomethionine and selenoethionine. Amino acids with the next chalcogen down are also found in nature: several species such as Aspergillus fumigatus
Non-proteinogenic_amino_acids
Chemical compounds containing selenium
have been used as specialty solvents. Analogous to the behavior of other chalcogens, selenium forms hydrogen selenide, H2Se. It is a strongly odiferous, toxic
Selenium_compounds
Chemical compounds containing phosphorus bound to a halogen
although serious doubts have been cast on the existence of PI5. Mixed chalcogen halides also exist. In the gas phase the phosphorus pentahalides have
Phosphorus_halide
Chemical compound
selenium, tellurium forms families of polymeric subhalides where the halide/chalcogen ratio is less than 2. Te2Br is a gray solid. Its structure consists of
Ditellurium_bromide
Index of chemical compounds with the same name
Developments in Binary Halogen–Chalcogen Compounds, Polyanions and Polycations". In Devillanova, Francesco (ed.). Handbook of Chalcogen Chemistry: New Perspectives
Tellurium_chloride
Any chemical compound containing at least one tellurium atom
compounds containing the element tellurium (Te). Tellurium belongs to the chalcogen (group 16) family of elements on the periodic table, which also includes
Tellurium_compounds
Elements predicted but not found in 1869
(alkaline earth metals) 3 4 5 6 7 8 9 10 11 12 13 14 15 (pnictogens) 16 (chalcogens) 17 (halogens) 18 (noble gases) Periods (1–7, ...) 1 2 3 4 5 6 7 8+ Blocks
Mendeleev's predicted elements
Mendeleev's_predicted_elements
Class of positively-charged molecules
mononuclear parent hydride of a pnictogen (group 15 of the periodic table), chalcogen (group 16), or halogen (group 17). The oldest-known onium ion, and the
Onium_ion
Chemical element with atomic number 13 (Al)
hydrogen chalcogenide. As aluminium is a small atom relative to these chalcogens, these have four-coordinate tetrahedral aluminium with various polymorphs
Aluminium
Mineral supergroup
in the cubic (isometric) crystal system, with the X anions (typically chalcogens, like oxygen and sulfur) arranged in a close-packed cubic lattice and
Spinel_group
Smallest unit of a chemical element
ellipsoidal deformations have been shown to occur for sulfur ions and chalcogen ions in pyrite-type compounds. Atomic dimensions are thousands of times
Atom
Chemical compound
Trioxidane (systematically named dihydrogen trioxide,), also called hydrogen trioxide is an inorganic compound with the chemical formula H2O3 or O(OH)2
Trioxidane
Index of chemical compounds with the same name
of these elements are transition metals, three are actinides, four are chalcogens, and one is a noble gas. Most hexafluorides are molecular compounds with
Hexafluoride
Chemical element with atomic number 82 (Pb)
chloride layer reduces further reactivity. Molten lead combines with the chalcogens to produce lead(II) chalcogenides. The metal resists attack by sulfuric
Lead
Chemical element with atomic number 8 (O)
it has the symbol O and its atomic number is 8. It is a member of the chalcogen group in the periodic table. It is highly reactive, a nonmetal, and a
Oxygen
Chemical compound
KCl KClO KClO2 KClO3 KClO4 KCN KCNO KF KHF2 KH KI KIO3 KIO4 KOCN KSCN chalcogens K2O KOH K2O2 KO2 KO3 K2S KHS K2SO3 KHSO3 K2SO4 KHSO4 KHSO5 K2S2O3 K2S2O5
Monopotassium_phosphate
Chemical compound
Ca(ClO)2 Ca(ClO3)2 Ca(ClO4)2 CaClOH CaBr2 Ca(BrO3)2 CaI2 Ca(IO3)2 CaICl Chalcogens CaO CaO2 Ca(OH)2 CaS CaSO3 CaH2S2O6 CaSO4 CaSe Pnictogens Ca3N2 CaN6 Ca(NO2)2
Calcium_hypochlorite
Chemical substance not composed of simpler ones
(alkaline earth metals) 3 4 5 6 7 8 9 10 11 12 13 14 15 (pnictogens) 16 (chalcogens) 17 (halogens) 18 (noble gases) Periods (1–7, ...) 1 2 3 4 5 6 7 8+ Blocks
Chemical_element
Chemical element with atomic number 30 (Zn)
associated with sulfur and other heavy chalcogens, rather than with the light chalcogen oxygen or with non-chalcogen electronegative elements such as the
Zinc
System for naming organic chemical compounds
Simple cations formed by adding a hydron to a hydride of a halogen, chalcogen or pnictogen are named by adding the suffix "-onium" to the element's
IUPAC nomenclature of organic chemistry
IUPAC_nomenclature_of_organic_chemistry
Class of chemical compound
Gold chalcogenides are compounds formed between gold and one of the chalcogens, elements from group 16 of the periodic table: oxygen, sulfur, selenium
Gold_chalcogenides
Chemical compound
LiIO4 Oxides and hydroxides LiO− LiO2 LiO3 Li2O Li2O2 LiOH Compounds with chalcogens LiCF3SO3 LiHSO3 LiHSO4 Li2Po Li2S Li2Se Li2SeO3 Li2SeO4 Li2Te LiTe3 Li2TeO3
Lithium_orotate
Metamorphic rock containing lazurite, prized for its intense blue color
Reinen, Dirk; Lindner, Gottlieb-Georg (1999-01-01). "The nature of the chalcogen colour centres in ultramarine-type solids". Chemical Society Reviews.
Lapis_lazuli
"Recent Developments in Binary Halogen–Chalcogen Compounds, Polyanions and Polycations" in Handbook of Chalcogen Chemistry: New Perspectives in Sulfur
Subhalide
Chemical compound
revaprazan, and dasantafil. The cyanamide anion has the character of a pseudo chalcogen, cyanamide can therefore be regarded as analogue to water or hydrogen
Cyanamide
Radius of an atomic ion in crystals
pyrite-type compounds, where monovalent chalcogen ions reside on C3 lattice sites. It was found that chalcogen ions have to be modeled by ellipsoidal charge
Ionic_radius
Chemical compound
MgF2 MgCl2 Mg(ClO3)2 Mg(ClO4)2 MgClOH MgBr2 MgI2 MgH2 Mg(OH)2 Mg(CN)2 Chalcogens MgO MgO2 MgS MgSO3 MgSO4 MgSe MgPo Pnictogens Mg3N2 Mg(NO3)2 Mg(H2PO4)2
Magnesium_trisilicate
Organic compounds that contain sulfur
removal of which is a major focus of oil refineries. Sulfur shares the chalcogen group with oxygen, selenium, and tellurium, and it is expected that organosulfur
Organosulfur_chemistry
Chemical compound
nearest environment of neodymium in glasses based on the gallium-germanium-chalcogen system". Glass Phys. Chem. 24: 446. Klenovskii, M.S.; Kel'man, V.A.; Zhmenyak
Caesium_chloride
Potassium compound and alternative to salt
KCl KClO KClO2 KClO3 KClO4 KCN KCNO KF KHF2 KH KI KIO3 KIO4 KOCN KSCN chalcogens K2O KOH K2O2 KO2 KO3 K2S KHS K2SO3 KHSO3 K2SO4 KHSO4 KHSO5 K2S2O3 K2S2O5
Potassium_chloride
Chemical element with atomic number 56 (Ba)
As expected for a highly electropositive metal, barium's reaction with chalcogens is highly exothermic (release energy). Barium reacts with atmospheric
Barium
Chemical element with atomic number 93 (Np)
iodide NpI3 has also been prepared by the same method as NpBr3. Neptunium chalcogen and pnictogen compounds have been well studied primarily as part of research
Neptunium
American chemist and University Administrator
McCullough, Richard Dean (1988). Synthesis and development of heterocyclic chalcogen pi-donor molecules as components for organic metals (PhD). Baltimore,
Richard_D._McCullough
Canadian inorganic chemist
Chivers and his colleagues made 'notable contributions' to the chemistry of chalcogen compounds. One early finding was to identify the blue species formed by
Tristram_Chivers
Poisonous and flammable gas
Namibia. Hydrogen chalcogenide – Chemical compound with hydrogen and chalcogen atoms Hydrogen sulfide chemosynthesis Marsh gas Sewer gas – Gases produced
Hydrogen_sulfide
Chemical element with atomic number 12 (Mg)
MgF2 MgCl2 Mg(ClO3)2 Mg(ClO4)2 MgClOH MgBr2 MgI2 MgH2 Mg(OH)2 Mg(CN)2 Chalcogens MgO MgO2 MgS MgSO3 MgSO4 MgSe MgPo Pnictogens Mg3N2 Mg(NO3)2 Mg(H2PO4)2
Magnesium
Chemical compound
Watkin, David J. (2000). "Group 6 transition metal carbonyl complexes with chalcogen-bridged diarsenic(III) ligands". Journal of the Chemical Society, Dalton
Cacodyl_oxide
Crystalline chemical element or compound formed by geologic processes
minerals are chemical compounds of one or more metals or semimetals with a chalcogen or pnictogen, of which sulfur is most common. Tellurium, arsenic, or selenium
Mineral
MgF2 MgCl2 Mg(ClO3)2 Mg(ClO4)2 MgClOH MgBr2 MgI2 MgH2 Mg(OH)2 Mg(CN)2 Chalcogens MgO MgO2 MgS MgSO3 MgSO4 MgSe MgPo Pnictogens Mg3N2 Mg(NO3)2 Mg(H2PO4)2
Magnesium_compounds
Comparison of the properties of the three main categories in the periodic table
ISBN 0-12-352651-5 Wickleder MS 2007, 'Chalcogen-oxygen chemistry', in FA Devillanova (ed.), Handbook of chalcogen chemistry: new perspectives in sulfur
Properties of metals, metalloids and nonmetals
Properties_of_metals,_metalloids_and_nonmetals
Chemical compound
Hydrogen peroxide is a chemical compound with the formula H2O2. In its pure form, it is a very pale blue liquid; however, at lower concentrations, it appears
Hydrogen_peroxide
Period Hydrogen and alkali metals Alkaline earth metals Pnictogens Chalcogens Halogens Noble gases ① Isotopes § List H 1 Isotopes § List He 2 ② Isotopes
Isotopes_of_neptunium
Alkali/bases Lanthanide/Actinide other metals Coal, oil or oil slate Chalcogen/Halogen other non-metal stone, crystals and complex compounds "Ichinokawa
List_of_mines_in_Japan
Chemical compound
thiophene, electrophiles tend to attack at the carbon positions next to the chalcogen. Such reactions are slower than that of furan, but faster than thiophene
Selenophene
Glass containing one or more of sulfur, selenium and tellurium
glass containing one or more heavy chalcogens (sulfur, selenium or tellurium; polonium is also a heavy chalcogen but too radioactive to use). Chalcogenide
Chalcogenide_glass
Tendency of an atom to attract a shared pair of electrons
metals) 3 4 5 6 7 8 9 10 11 12 13 (Triels) 14 (Tetrels) 15 (Pnictogens) 16 (Chalcogens) 17 (Halogens) 18 (Noble gases) Periods 1 2 3 4 5 6 7 8+ Aufbau Fricke
Electronegativity
Chemical compound
August 2025. Chivers, Tristram; Laitinen, Risto S. (12 October 2021). Chalcogen-nitrogen Chemistry: From Fundamentals To Applications In Biological, Physical
Fluorosulfonyl_azide
Group of highly reactive chemical elements
with an excess of the chalcogen can similarly result in lower chalcogenides, with chalcogen ions containing chains of the chalcogen atoms in question. For
Alkali_metal
Intermolecular attraction between a hydrogen donor-and-acceptor pair
of electrons in nonmetallic atoms (most notably in the nitrogen, and chalcogen groups). In some cases, these proton acceptors may be pi-bonds or metal
Hydrogen_bond
Column of elements in the periodic table of the chemical elements
example, group 16 is also described as the "oxygen group" and as the "chalcogens". An exception is the "iron group", which usually refers to group 8, but
Group_(periodic_table)
Inorganic compound (KOH)
KCl KClO KClO2 KClO3 KClO4 KCN KCNO KF KHF2 KH KI KIO3 KIO4 KOCN KSCN chalcogens K2O KOH K2O2 KO2 KO3 K2S KHS K2SO3 KHSO3 K2SO4 KHSO4 KHSO5 K2S2O3 K2S2O5
Potassium_hydroxide
Chemical compound
Tristram; Laitinen, Risto S. (2006). "Chalcogen–Nitrogen Chemistry". In Devillanova, Francesco (ed.). Handbook of Chalcogen Chemistry. London: The Royal Society
Thiazyl_trifluoride
Chemical element with atomic number 20 (Ca)
metallic calcium is in steelmaking, due to its strong chemical affinity for chalcogens oxygen and sulfur. Its oxides and sulfides, once formed, give liquid lime
Calcium
Chemical compound
LiIO4 Oxides and hydroxides LiO− LiO2 LiO3 Li2O Li2O2 LiOH Compounds with chalcogens LiCF3SO3 LiHSO3 LiHSO4 Li2Po Li2S Li2Se Li2SeO3 Li2SeO4 Li2Te LiTe3 Li2TeO3
Lithium_phosphate
Organosulfur compounds with an >NC(=S)N< structure
PMID 22435999. Nieuwland, Celine; Fonseca Guerra, Célia (2022). "How the Chalcogen Atom Size Dictates the Hydrogen-Bond Donor Capability of Carboxamides
Thioureas
Period Hydrogen and alkali metals Alkaline earth metals Pnictogens Chalcogens Halogens Noble gases ① Isotopes § List H 1 Isotopes § List He 2 ② Isotopes
Isotopes_of_tungsten
Chemical compound
LiIO4 Oxides and hydroxides LiO− LiO2 LiO3 Li2O Li2O2 LiOH Compounds with chalcogens LiCF3SO3 LiHSO3 LiHSO4 Li2Po Li2S Li2Se Li2SeO3 Li2SeO4 Li2Te LiTe3 Li2TeO3
Lithium_hydride
Chemical element with atomic number 32 (Ge)
Bi4Ge3O12 (BGO), is used as a scintillator. Binary compounds with other chalcogens are also known, such as the disulfide (GeS2) and diselenide (GeSe2), and
Germanium
Chemical compound
dichalcogenides, compounds that consist of a metal and an element of the chalcogen column within the periodic table. Many exhibit properties of potential
Titanium_diselenide
Chemical compound
ISBN 978-0-470-84289-8. Devillanova, Franceso A. (2007). Handbook of Chalcogen Chemistry: New Perspectives in Sulfur, Selenium and Tellurium. Royal Society
Selenium_dioxide
Solids with high anisotropic bonding
layered materials are metal dichalcogenides. In such materials, the M-chalcogen bonding is strong and covalent. These materials exhibit anisotropic electronic
Layered_materials
Assembly of molecules or ions
Gutmann, Childs, Beckett, and the ECW model. Many organic species featuring chalcogen or pnictogen donor atoms form CT salts. The nature of the resulting adducts
Charge-transfer_complex
Series of chemical elements
(alkaline earth metals) 3 4 5 6 7 8 9 10 11 12 13 14 15 (pnictogens) 16 (chalcogens) 17 (halogens) 18 (noble gases) Periods (1–7, ...) 1 2 3 4 5 6 7 8+ Blocks
Transition_metal
Chemical compound
Selenous acid (or selenious acid) is the chemical compound with the formula H2SeO3. Structurally, it is more accurately described by O=Se(OH)2. It is the
Selenous_acid
Chemical compound
1980, volume 460, pp. 81–85. doi:10.1002/zaac.19804600108 Handbook of Chalcogen Chemistry: New Perspectives in Sulfur, Selenium and Tellurium, Francesco
Selenium_trioxide
Identical electron configuration
all valence isoelectronic to each other. They differ by which specific chalcogen is present at one location in the side-chain. CH 3COCH 3 (acetone) and
Isoelectronicity
Chemical compound
Developments in Binary Halogen–Chalcogen Compounds, Polyanions and Polycations". In Devillanova, Francesco (ed.). Handbook of Chalcogen Chemistry: New Perspectives
Tritellurium_dichloride
Chemical compound of calcium
Ca(ClO)2 Ca(ClO3)2 Ca(ClO4)2 CaClOH CaBr2 Ca(BrO3)2 CaI2 Ca(IO3)2 CaICl Chalcogens CaO CaO2 Ca(OH)2 CaS CaSO3 CaH2S2O6 CaSO4 CaSe Pnictogens Ca3N2 CaN6 Ca(NO2)2
Calcium_oxide
Chemical salt used in cooking as cream of tartar
KCl KClO KClO2 KClO3 KClO4 KCN KCNO KF KHF2 KH KI KIO3 KIO4 KOCN KSCN chalcogens K2O KOH K2O2 KO2 KO3 K2S KHS K2SO3 KHSO3 K2SO4 KHSO4 KHSO5 K2S2O3 K2S2O5
Potassium_bitartrate
Period Hydrogen and alkali metals Alkaline earth metals Pnictogens Chalcogens Halogens Noble gases ① Isotopes § List H 1 Isotopes § List He 2 ② Isotopes
Isotopes_of_californium
Chemical compound
Oxides and hydroxides Cs2O Cs2O2 Cs2O3 CsO2 CsO3 CsOH Compounds with chalcogens Cs2S Cs2SO4 CsHSO4 Cs2Se Cs2SeO4 Cs2Te Compounds with pnictogens CsN3
Caesium_zirconate
Chemical compound
LiIO4 Oxides and hydroxides LiO− LiO2 LiO3 Li2O Li2O2 LiOH Compounds with chalcogens LiCF3SO3 LiHSO3 LiHSO4 Li2Po Li2S Li2Se Li2SeO3 Li2SeO4 Li2Te LiTe3 Li2TeO3
Lithium_fluoride
Class of chemical compounds
produce imidoyl chlorides from other substrates. Generally the halogen-chalcogen exchange proceeds better for thioamides, but thioamides are more difficult
Imidoyl_chloride
Chemical compound
KCl KClO KClO2 KClO3 KClO4 KCN KCNO KF KHF2 KH KI KIO3 KIO4 KOCN KSCN chalcogens K2O KOH K2O2 KO2 KO3 K2S KHS K2SO3 KHSO3 K2SO4 KHSO4 KHSO5 K2S2O3 K2S2O5
Potassium_osmate
Severe neurological disease caused by mercury poisoning
including lead, mercury, manganese, arsenic, thallium, and copper, plus the chalcogen selenium. Identifying which particular poison was responsible for the
Minamata_disease
Period Hydrogen and alkali metals Alkaline earth metals Pnictogens Chalcogens Halogens Noble gases ① Isotopes § List H 1 Isotopes § List He 2 ② Isotopes
Isotopes_of_boron
Chemical compound
Ca(ClO)2 Ca(ClO3)2 Ca(ClO4)2 CaClOH CaBr2 Ca(BrO3)2 CaI2 Ca(IO3)2 CaICl Chalcogens CaO CaO2 Ca(OH)2 CaS CaSO3 CaH2S2O6 CaSO4 CaSe Pnictogens Ca3N2 CaN6 Ca(NO2)2
Calcium_gluconate
Non metallic elements
metalloid. The size of the group 14 set, and the sets of nonmetal pnictogens, chalcogens, and halogens will vary depending on how silicon, germanium, arsenic,
List of alternative nonmetal classes
List_of_alternative_nonmetal_classes
CHALCOGEN
CHALCOGEN
CHALCOGEN
CHALCOGEN
Boy/Male
Tamil
Morality, Superior
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Blissful Kingdom
Girl/Female
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Surname or Lastname
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English : variant of Swallow.
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CHALCOGEN
CHALCOGEN
CHALCOGEN
CHALCOGEN
CHALCOGEN