Synthesis, Crystal Structure, and Spectroscopic Characterization of Na5[NiO2][CO3], containing the Linear [NiO2]3- Group with Monovalent Nickel

Abstract

For the first time ruby-red single crystals and powder samples of Na 5 [NiO 2 ][CO 3 ] were obtained via a redox reaction between nickel metal and CdO in the presence of Na 2 O and Na 2 CO 3 (molar ratios of CdO : Na 2 O : Na 2 CO 3 equal 1 : 3 : 2). The crystal structure has been refined from single crystal X-ray diffraction data at 170 K (tetragonal, P4/ mmm, a = 462.7(1) pm, c = 830.5(2) pm) and at 293 K (a = 462.35 (7) pm, c = 830.9(1) pm). Na 5 [NiO 2 ][CO 3 ] is the first example of an alkaline-rich transition metal oxide with two different oxoanions, [NiO 2 ] 3± and [CO 3 ] 2± , coexisting in one compound. The electronic spectrum of Na 5 [NiO 2 ][CO 3 ] has been measured between 4000 and 25000 cm ±1 . Two d-d-transitions of the linear [NiO 2 ] 3± complex (d 9 ) are observed at 5870 cm ±1 and 11850 cm ±1 and analysed using the angular overlap model. MIR and FIR spectra give evidence for the [CO 3 ] 2± anion present in the structure. Pra È paration, Kristallstruktur und spektroskopische Charakterisierung von Na 5 [NiO 2 ][CO 3 ] mit der linearen [NiO 2 ] 3± -Einheit mit einwertigem Nickel Inhaltsu È bersicht. Erstmals wurden rubinrote Einkristalle und Pulverproben von Na 5 [NiO 2 ][CO 3 ] durch Redoxreaktion zwischen metallischem Nickel und CdO in Gegenwart von Na 2 O und Na 2 CO 3 erhalten (molares Verha È ltnis CdO : Na 2 O : Na 2 CO 3 von 1 : 3 : 2). Die Kristallstruktur wurde bei 170 K (tetragonal, P4/mmm, a = 462.7(1) pm, c = 830.5(2) pm) und bei 293 K (a = 462.35(7) pm, c = 830.9(1) pm) mit Ro È ntgen-Einkristallmethoden bestimmt. Mit Na 5 [NiO 2 ][CO 3 ] ist erstmals ein Vertreter der alkalirei-chen polyna È ren Ûbergangsmetalloxide mit zwei nebeneinander vorliegenden Oxoanionen, [NiO 2 ] 3± und [CO 3 ] 2± , gefunden worden. Das elektronische Spektrum zeigt zwischen 4000 und 25000 cm ±1 zwei d-d-Ûberga È nge bei 5870 und 11850 cm ±1 , die dem linearen Ûbergangsmetallkomplex, [NiO 2 ] 3± (d 9 ), zugeordnet und im Rahmen des Angular-Overlap-Modells interpretiert werden ko È nnen. MIR und FIR Spektren besta È tigen das Vorliegen von [CO 3 ] 2± in der Struktur.

Fabrication of a Ni-Cu Thin Film Material Library Using Pulsed Electrodeposition

“…5a) with rather low intensities were observed at 2θ = 47.39 • , 2θ = 48.19 • and 2θ = 108.28 • . These peaks correspond to the (104), (212) and (208) plane of a slight off-stoichiometric Na 5 Ni[CO 3 ]O 2 phase, 42 This phase developed with growing Ni content and contained further elements from the electrodeposition bath ingredients. However, this precipitation phase appears only in a very small quantity in the presented alloy library.…”