Product Code Database
Arsenic trisulfide is the inorganic compound with the formula . It is a dark yellow solid that is insoluble in water. It also occurs as the mineral orpiment (Latin: auripigmentum), which has been used as a pigment called King's yellow. It is produced in the analysis of arsenic compounds. It is a group V/VI, intrinsic p-type semiconductor and exhibits photo-induced phase-change properties.
occurs both in crystalline and amorphous forms. Both forms feature polymeric structures consisting of trigonal pyramidal As(III) centres linked by sulfide centres. The sulfide centres are two-fold coordinated to two arsenic atoms. In the crystalline form, the compound adopts a ruffled sheet structure.Wells, A.F. (1984). Structural Inorganic Chemistry, Oxford: Clarendon Press. . The bonding between the sheets consists of van der Waals forces. The crystalline form is usually found in geological samples. Amorphous does not possess a layered structure but is more highly cross-linked. Like other [[glass]]es, there is no medium or long-range order, but the first co-ordination sphere is well defined. is a good [[glass former|glass formation]] and exhibits a wide glass-forming region in its [[phase diagram]].
forms when aqueous solutions containing As(III) are treated with . Arsenic was in the past analyzed and assayed by this reaction, which results in the precipitation of , which is then weighed. can even be precipitated in 6 M HCl. is so insoluble that it is not toxic.
characteristically dissolves upon treatment with aqueous solutions containing [[sulfide]] ions. The dissolved arsenic species is the pyramidal [[trithioarsenite]] [[anion]] :
is the anhydride of the hypothetical trithioarsenous acid, . Upon treatment with [[polysulfide]] ions, dissolves to give a variety of species containing both S–S and As–S bonds. One derivative is , an eight-membered ring that contains 7 S atoms and 1 As atom, and an [[exocyclic]] [[sulfido]] center attached to the As atom. also dissolves in strongly alkaline solutions to give a mixture of [[|trithioarsenite]] and [[|arsenite]].Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. .
"Roasting" in air gives volatile, toxic derivatives, this conversion being one of the hazards associated with the refining of heavy metal :
has been investigated for use as a high resolution photoresist material since the early 1970s,Zenkin, S. A.; Mamedov, S. B.; Mikhailov, M. D.; Turkina, E. Yu.; Yusupov, I. Yu. Glass Phys. Chem. 1997, 5, pp 393-399. using aqueous etchants. Although these aqueous etchants allowed for low-aspect ratio 2-D structures to be fabricated, they do not allow for the etching of high aspect ratio structures with 3-D periodicity. Certain organic reagents, used in organic solvents, permit the high-etch selectivity required to produce high-aspect ratio structures with 3-D periodicity.
and have been investigated as treatments for acute promyelocytic leukemia (APL).
Arsenic trisulfide was used for the distinctive eight-sided conical nose over the infra-red seeker of the de Havilland Firestreak missile.
Precipitation of arsenic trisulfide is used as an analytical test for presence of dissimilatory arsenic-reducing bacteria (DARB).Linping Kuai, Arjun A. Nair, and Martin F. Polz "Rapid and Simple Method for the Most-Probable-Number Estimation of Arsenic-Reducing Bacteria" Appl Environ Microbiol. 2001, vol. 67, 3168–3173. .
is so insoluble that its toxicity is low. Aged samples can contain substantial amounts of arsenic oxides, which are soluble and therefore highly toxic.
|
|
