Niobium compounds

Niobium muaj ntau txoj hauv kev zoo ib yam li tantalum thiab zirconium. Nws yuav hnov ​​​​mob nrog fluorine ntawm chav tsev kub, nrog cov tshuaj chlorine thiab hydrogen ntawm 200 degree, thiab nrog nitrogen ntawm 400 degree, cov khoom feem ntau yog interstitial non-integer ratio compounds. Niobium hlau oxidizes nyob rau hauv huab cua ntawm 200 degree thiab yog resistant rau molten bases thiab ntau yam acids, xws li aqua regia, hydrochloric, sulfuric, nitric, thiab phosphoric acids. Txawm li cas los xij, hydrofluoric acid thiab sib tov ntawm hydrofluoric thiab nitric acids tuaj yeem tua niobium.
Txawm hais tias niobium tuaj yeem tsim ntau yam sib xyaw nrog oxidation xeev xws li +5 rau -1, nws feem ntau pom nyob rau hauv +5 oxidation xeev. Niobium tebchaw nrog oxidation xeev hauv qab no +5 muaj niobium-niobium bonds.

Oxide thiab sulfides
Oxides ntawm niobium tuaj yeem muaj cov oxidation hauv qab no: +5 (Nb2O5), +4 (NbO2), thiab +3 (Nb2O3), ntxiv rau qhov tsis tshua muaj +2 xeev (NbO) . Niobium pentoxide yog niobium oxide ntau tshaj plaws uas niobium hlau thiab tag nrho cov niobium tebchaw tau npaj. Ua niobates, niobium pentoxide tuaj yeem yaj hauv cov tshuaj alkaline hydroxide los yog yaj hauv alkali hlau oxide. Lithium niobate (LiNbO3) muaj calcite-hom biotriangular siv lead ua kab ke qauv, thaum lanthanum niobate muaj cais NbO3- ions. Lwm cov ntsiab lus paub suav nrog niobium sulfide (NbS2), uas tsim cov txheej txheem txheej.
Cov txheej nyias nyias ntawm niobium pentoxide tuaj yeem muab ntxiv rau saum npoo ntawm cov khoom siv tshuaj vapor deposition lossis atomic txheej deposition, ob qho tib si siv lub hauv paus ntsiab lus uas ethanol niobium (V) thermally decomposes saum 350 degree.
Halides
Niobium tuaj yeem tsim halides nrog {{{0}}} thiab +4 oxidation xeev, nrog rau ntau yam sub-stoichiometric compounds. Niobium pentahalide (NbX5) muaj octahedral niobium central atom. Niobium pentafluoride (NbF5) yog cov khoom dawb nrog lub melting point ntawm 79.0 degree, thaum niobium pentachloride (NbCl5) yog xim daj nrog lub melting point ntawm 203.4 degree. Ob leeg tuaj yeem ua hydrolyzed los tsim oxides thiab halogenated oxides xws li NbOCl3. Niobium pentachloride kuj yog ib qho tshuaj reagent siv nyob rau hauv kev sib txuas ntawm ntau yam organometallic tebchaw, suav nrog niobium dichlorocene ((C5H5) 2NbCl2). Organometallic compounds. Cov tetrahalides ntawm niobium (NbX4) yog cov polymers tsaus uas muaj niobium-niobium bonds, xws li cov dub, hygroscopic niobium tetrafluoride (NbF4) thiab xim av niobium tetrachloride (NbCl4).
Tsis zoo halide ions ntawm niobium kuj tseem muaj, vim qhov tseeb tias pentahalides ntawm niobium yog tag nrho cov Lewis acids. Qhov tseem ceeb tshaj plaws yog [NbF7], uas yog qhov sib xyaw nruab nrab hauv cov txheej txheem ntawm kev sib cais cov zaub mov ntawm niobium thiab tantalum. Nws tau yooj yim hloov dua siab tshiab rau cov pa pentahalide ntau dua li cov tantalum sib txuas. Lwm cov halogenated complex muaj xws li [NbCl6]:
Nb2Cl10+ 2Cl → 2 [NbCl6].
Niobium kuj tsim ntau yam kev txo qis halide atom pawg, xws li [Nb6Cl18].
Nitrides thiab carbide
Niobium nitride (NbN) dhau los ua ib qho superconductor ntawm qhov kub thiab txias thiab siv rau hauv infrared detectors. Qhov tseem ceeb niobium carbide yog NbC, uas yog ib qho nyuaj heev, cov khoom siv refractory ceramic, thiab siv los ua cov cuab yeej siv me ntsis.