Chloride Derivatives of Lanthanide Ortho‐Oxomolybdates: 1. Structural Comparison, Magnetic Properties, and Luminescence of the LnCl[MoO₄] Representatives with the Smaller Lanthanides (Ln = Sm–Lu)

Abstract

The lanthanide chloride ortho-oxomolybdates LnCl[MoO 4 ] (Ln ϭ SmϪYb) crystallize in the monoclinic space group C2/m (a ϭ 1035Ϫ1010 pm, b ϭ 736Ϫ713 pm, c ϭ 691Ϫ678 pm, β ϭ 106.7Ϫ107.4°, Z ϭ 4), while LuCl[MoO 4 ] displays a triclinic structure (space group P1, a ϭ 591.42(2) pm, b ϭ 716.19(3) pm, c ϭ 681.44(3) pm, Ͱ ϭ 93.724(2)°, β ϭ 102.463°, γ ϭ 122.134 (2)°, Z ϭ 2). The isotypical monoclinic derivatives exhibit one crystallographically unique site for the lanthanide cations with a coordination number of eight (2 ϫ Cl Ϫ and 6 ϫ O 2Ϫ arranged as trigonal dodecahedra). The Lu 3ϩ cations in LuCl[MoO 4 ] also occupy a single crystallographic position, but with a coordination number of only seven (2 ϫ Cl Ϫ and 5 ϫ O 2Ϫ , arranged as monocapped trigonal prisms). The coordination polyhedra around the lanthanide cations in the LnCl[MoO 4 ] representatives (Ln ϭ SmϪYb) are connected to each other via three common edges, * Dr. I. Hartenbach

From Yellow to Black: Dramatic Changes between Cerium(IV) and Plutonium(IV) Molybdates

“…[36][37][38][39][40][41] Concurrently, lanthanide molybdates have also been investigated for their complex and interesting properties such as negative thermal expansion, ferroelectricity, ferroelasticity, photoluminescence, and interesting structure types. [42][43][44][45][46][47][48][49] Of particular interest is the compound Ce 2 MoO 6 of the Ln 2 MoO 6 series (Ln = La -Lu). Ce 2 MoO 6 is unusual with respect to the rest of the series as it adopts a black color while the others assume their typical colors and appears to adopt a structure unique to the series.…”

Syntheses and Crystal Structures of the Bromide-derivatized Lanthanoid(III) Ortho-Oxomolybdates(VI) LnBr[MoO4] (Ln = Pr, Nd, Sm, Gd– Lu)

“…Furthermore, the similarities and differences to the non-isotypic structures of the homologous series LnCl[MoO 4 ] (Ln = Pr [4], Nd [25], Sm -Lu [6]) and LnF [MoO 4 ] (Ln = Sm -Tm [2]) are shown in a detailed structural comparison, which includes a special consideration of their triclinic lattice constants as a function of the lanthanoid contraction.…”

“…Nonetheless, in the overall contraction process a steady, almost linear reduction of the molar volume with respect to the ionic radius of the shrinking Ln 3+ cation is observed (Fig. 5, bottom) 4 ] representatives with Ln = Nd [25] and Sm -Lu [6] three different structure types can be distinguished, in which the polyhedra around the Ln 3+ cations are condensed to form a three-(Ln = Nd [25]), two-(Ln = Sm -Yb [6]), or one-dimensional arrangement (Ln = Lu [6]), the fundamental architecture of the bromide homologs remains unchanged throughout the whole series presented here. The details, however, also reflect the course of the contracting coordination environment of the Ln 3+ cations.…”

Chloride derivatives of lanthanoid(III) ortho-oxidotungstates(VI) with the formula LnCl[WO4] (Ln=Gd–Lu): Syntheses, crystal structures and spectroscopic properties

“…Further details of the crystal structure investigations are available from the Fachinformationszentrum (FIZ) Karlsruhe, D-76344 Eggenstein-Leopoldshafen, Germany (Fax: þ49 7247 808 666; E-mail: crysdata@fiz-karlsruhe.de), upon citing the respective CSD-numbers from Tables 1 and 2. 4 ] were recorded at room temperature using a Horiba FluoroMax-4 fluorescence spectrometer equipped with a xenon discharge lamp scanning a range from 200 to 800 nm. Electronic transitions were assigned according to the energy-level diagrams of the trivalent europium and terbium cations, respectively [22].…”

“…Now it was possible to synthesize single crystals of the whole sequence of lanthanoid(III) chloride ortho-oxidotungstates(VI) with the formula LnCl[WO 4 ] for the smaller lanthanoid elements (Ln¼Gd-Lu) and to analyze structural and spectroscopic details. In the realm of formally analogous rare-earth metal(III) chloride oxidomolybdates(VI) RECl[MoO 4 ] with RE¼Y, Sm-Lu [3,4], as obvious close relatives of the respective tungstates, a structural gap within the LnCl[MoO 4 ] series for the smaller lanthanoids can be detected between ytterbium and lutetium [4]. The representatives of these molybdates from gadolinium to ytterbium crystallize monoclinically, thus isotypically to the monoclinic structure of the respective chloride oxidotungstates in the present paper.…”