Secontaining

Secontaining is a neologism used to describe any substance that includes at least one selenium atom in its chemical composition. In practice, most scientists would write selenium-containing or Se-containing; Secontaining appears in certain databases, glossaries, or shorthand, and is intended as a concise label rather than a formal class.

Secontaining compounds span inorganic and organic chemistry. Inorganic species include selenides (R-Se-R'), selenites (SeO3^2-), and selenates (SeO4^2-). Organoselenium compounds include selenides, diselenides, selenols (R-Se-H), and selenoethers (R-Se-R'). In biology, Se-containing biomolecules include selenocysteine and selenomethionine.

Se-containing materials are used in electronics and optics; crystalline selenium has historical use in rectifiers and photoconductors, and selenium is a component of chalcogenide glasses for infrared optics. In biology, selenium is essential in certain enzymes as part of the active selenocysteine residue, and Se-containing amino acids such as selenomethionine occur in some foods.

Se-containing species display variable oxidation states from -2 to +6 and often exhibit redox activity, modified electronic structures, and distinctive optical properties compared with analogous sulfur compounds. Synthesis and incorporation of Se into molecules commonly involve substitution or addition reactions, oxidation of selenol precursors, or coupling with elemental selenium, depending on the target class.

Many selenium compounds can be toxic in excess; handling requires standard chemical safety practices, and waste disposal must follow applicable regulations and guidelines.