Oxyarsenides or arsenide oxides are chemical compounds formally containing the group AsO, with one arsenic and one oxygen atom. The arsenic and oxygen are not bound together as in arsenates or arsenites, instead they make a separate presence bound to the cations (metals), and could be considered as a mixed arsenide-oxide compound. So a compound with OmAsn requires cations to balance a negative charge of 2m+3n. The cations will have charges of +2 or +3. The trications are often rare earth elements or actinides. They are in the category of oxypnictide compounds.
Some of these compounds are superconductors, but may require doping with fluoride or oxygen deficiency. Yet others undergo colossal magnetoresistance with a lowered electrical resistance in a magnetic field.
Many compounds are layered, containing two metals with the formula XZAsO, with an XAs layer alternating with a ZO layer.
Examples formulanamemwstructurespace groupcellappearancepropertiessupercondicting TcreferenceSr2Cr3As2O3tetragonalP4/mmma=4.04032 c=9.33140 V=152.327Sr2Cr2AsO3tetragonalP4/nmma=3.90988 c=16.05417 C=245.422Sr2Mn3As2O2a=4.1459 c=18.856Sr2Cr1.85Mn1.15As2O2tetragonalI4/mmma = 4.043788 c 18.9977 Z=2 V=310.654Sr2CrO3FeAstetragonalSr2CrO3CrAsP4/nmma=3.90988 c=16.05417 V=245.422Sr2CrO2Cr2OAs2P4/mmma=4.04032 c=9.33140 V=152.327Sr2MnZn2As2O2 a=4.12624 c=18.6709YFeAsOyttrium iron oxyarsenidetetragonalferromagnetic 62KBa2Ti2OAs2Cr2As2tetragonalI4/nmma=4.0391 c=27.8474Ba2Ti2Fe2As4OtetragonalI4/nmmsuperconductorBaTi2As2OtetragonalI4/nmma = 4.047 c = 7.275density wave at 200KBa2MnZn2As2O2 tetragonalP4/nmma=4.23369 c=19.5087LaMnAsOLaCoAsOLaFeAsO1−xFxfluorine doped Lanthanum iron oxyarsenidetetragonal26KLaNiOAsLanthanum Nickel oxyarsenidetetragonalP4/nmmmetallic2.4PrFeAsOPraseodymium iron oxyarsenideNdMnAsONdMnAsO0.95F0.05a=4.04870 c=8.89654NdFeAsONeodymium iron oxyarsenideNd0.9Sr0.1MsAsOSmFeAsO0.9F0.1Samarium iron oxyarsenidetetragonal55KTbFeAsOTerbium iron oxyarsenidetetragonalsuperconductingTbFeAsO0.85 tetragonala = 3.889 Å b = 8.376 42TbRuAsOterbium ruthenium arsenide oxide350.95tetragonalP4/nmma= 4.0254 c=8.0710 V=130.782 Z=2greyDyRuAsOdysprosium ruthenium arsenide oxide354.49tetragonalP4/nmma=4.01728 c=8.03272 V=129.637 Z=2greyDyRuAsOdysprosium ruthenium arsenide oxide354.49orthorhombica=4.02033 b=4.00791 c=8.0048 V=128.983 Z=2at 12KGd0.8Th0.2FeAsOthorium doped gadolinium iron oxyarsenidetetragonal55KU2Cu2As3Odiuranium dicopper oxytriarsenideP4/nmma = 3.9111 Å c = 17.916 Z=2
Related Related compounds include the oxynitrides, oxyphosphides, oxyantimonides and oxybismuthides.
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