Browsing by Author "Schleid, Thomas"

Now showing 1 - 20 of 38

Open Access
A-type Ce2NCl3
(2011) Schurz, Christian M.; Schleid, Thomas
The crystal structure of cerium nitride chloride (A-type) as well as the synthesis method is described in this paper.
Open Access
About lanthanoid fluoride selenide oxoselenotantalates with the composition Ln3F2Se2TaO4 (Ln = La - Nd)
(2020) Grossholz, Hagen; Buyer, Constantin; Lotter, Sebastian M. A.; Wolf, Sarah; Schleid, Thomas
After solid-state reactions of the light lanthanoid metals, their oxides and fluorides as well as selenium in sealed tantalum ampoules with sodium chloride as a fluxing agent at 850 °C for 8 days needle-shaped single crystals of Ln3F2Se2TaO4 (Ln = La - Nd) were obtained. They crystallize in the orthorhombic space group Pnma analogous to La3F2Se2NbO4 with a = 1133-1120 pm, b = 400-393 pm and c = 1812-1778 pm (Ln = La - Nd) for Z = 4 as the first known quinary lanthanoid(III) oxoselenotantalates(V) with fluoride and selenide anions. The three crystallographically different Ln3+ cations are all surrounded by nine anions (O2-, F- and Se2-) each. Tantalum resides in an octahedral chalcogen coordination by forming trans-vertex oxygen-connected [TaO5Se]7- polyhedra, which build up chains 1∞{[TaOV2/2Ot3/1Set1/1]5-} along [010]. The sites of the four crystallographically different oxygen atoms and the two distinct fluoride anions were established by bond-valence calculations. One fluorine and three oxygen atoms are surrounded tetrahedrally by cations, while another fluoride and oxide anion exhibit just triangular non-planar coordination spheres. The two independent Se2- anions have five or six cationic neighbors.
Open Access
A challenge toward novel quaternary sulfides SrLnCuS3 (Ln = La, Nd, Tm) : unraveling synthetic pathways, structures and properties
(2022) Ruseikina, Anna V.; Grigoriev, Maxim V.; Solovyov, Leonid A.; Chernyshev, Vladimir A.; Aleksandrovsky, Aleksandr S.; Krylov, Alexander S.; Krylova, Svetlana N.; Shestakov, Nikolai P.; Velikanov, Dmitriy A.; Garmonov, Alexander A.; Matigorov, Alexey V.; Eberle, Marcel A.; Schleid, Thomas; Safin, Damir A.
We report on the novel heterometallic quaternary sulfides SrLnCuS3 (Ln = La, Nd, Tm), obtained as both single crystals and powdered samples. The structures of both the single crystal and powdered samples of SrLaCuS3 and SrNdCuS3 belong to the orthorhombic space group Pnma but are of different structural types, while both samples of SrTmCuS3 crystallize in the orthorhombic space group Cmcm with the structural type KZrCuS3. Three-dimensional crystal structures of SrLaCuS3 and SrNdCuS3 are formed from the (Sr/Ln)S7 capped trigonal prisms and CuS4 tetrahedra. In SrLaCuS3, alternating 2D layers are stacked, while the main backbone of the structure of SrNdCuS3 is a polymeric 3D framework [(Sr/Ln)S7]n, strengthened by 1D polymeric chains (CuS4)n with 1D channels, filled by the other Sr2+/Ln3+ cations, which, in turn, form 1D dimeric ribbons. A 3D crystal structure of SrTmCuS3 is constructed from the SrS6 trigonal prisms, TmS6 octahedra and CuS4 tetrahedra. The latter two polyhedra are packed together into 2D layers, which are separated by 1D chains (SrS6)n and 1D free channels. In both crystal structures of SrLaCuS3 obtained in this work, the crystallographic positions of strontium and lanthanum were partially mixed, while only in the structure of SrNdCuS3, solved from the powder X-ray diffraction data, were the crystallographic positions of strontium and neodymium partially mixed. Band gaps of SrLnCuS3 (Ln = La, Nd, Tm) were found to be 1.86, 1.94 and 2.57 eV, respectively. Both SrNdCuS3 and SrTmCuS3 were found to be paramagnetic at 20-300 K, with the experimental magnetic characteristics being in good agreement with the corresponding calculated parameters.
Open Access
Composition and crystal structure of SmSb2O4Cl revisited : and the analogy of Sm1.5Sb1.5O4Br
(2019) Goerigk, Felix C.; Schleid, Thomas
The quaternary halide‐containing samarium(III) oxidoantimonates(III) Sm1.3Sb1.7O4Cl and Sm1.5Sb1.5O4Br were synthesized through solid‐state reactions from the binary components (Sm2O3, Sb2O3 and SmX3, X = Cl and Br) at 750 °C in evacuated fused silica ampoules. They crystallize tetragonally in the space group P4/mmm, like the basically isotypic bismuthate(III) compounds SmBi2O4Cl and SmBi2O4Br, but show larger molar volumes and therefore contradict an ideal composition of “SmSb2O4X” (X = Cl and Br). Both single‐crystal X‐ray diffraction and quantitative electron‐beam microprobe analysis revealed the actual compositions of the investigated antimony(III) compounds, which can be understood as heavily Sm3+‐doped derivatives of “SmSb2O4X” hosts at the Sb3+ site. (Sm1)3+ is coordinated eightfold by oxygen atoms in the shape of a cube. The mixed‐occupied (Sb/Sm2)3+ cation has four oxygen atoms and four halide anions as neighbors forming a square antiprism. The oxygen atoms and anions establish alternating layers parallel to the ab‐plane, which alternate when stacked along [001].
Open Access
The crystal structures of two hydro-closo-borates with divalent tin in comparison : Sn(H2O)3[B10H10] · 3 H2O and Sn(H2O)3[B12H12] · 4 H2O
(2021) Kleeberg, Fabian M.; Zimmermann, Lucas W.; Schleid, Thomas
Single crystals of Sn(H2O)3[B10H10] · 3 H2O and Sn(H2O)3[B12H12] · 4 H2O are easily accessible by reactions of aqueous solutions of the acids (H3O)2[B10H10] and (H3O)2[B12H12] with an excess of tin metal powder after isothermal evaporation of the clear brines. Both compounds crystallize with similar structures in the triclinic system with space group P1¯ and Z = 2. The crystallographic main features are electroneutral 1∞{Sn(H2O)3/1[B10H10]3/3} and 1∞{ Sn(H2O)3/1[B12H12]3/3} double chains running along the a-axes. Each Sn2+ cation is coordinated by three water molecules of hydration (d(Sn-O) = 221-225 pm for the B10 and d(Sn-O) = 222-227 pm for the B12 compound) and additionally by hydridic hydrogen atoms of the three nearest boron clusters (d(Sn-H) = 281-322 pm for the B10 and d(Sn-H) = 278-291 pm for the B12 compound), which complete the coordination sphere. Between these tin(II)-bonded water and the three or four interstitial crystal water molecules, classical bridging hydrogen bonds are found, connecting the double chains to each other. Furthermore, there is also non-classical hydrogen bonding between the anionic [BnHn]2- (n = 10 and 12) clusters and the crystal water molecules pursuant to B-Hδ-⋯δ+H-O interactions often called dihydrogen bonds.
Open Access
Cs3Sm7Se12
(2012) Schneck, Christof; Elbe, Andreas; Schurz, Christian M.; Schleid, Thomas
The crystal structure of Cs3Sm7Se12 is described in the paper.
Open Access
Defect scheelite-type lanthanoid(III) ortho-oxomolybdates(VI) Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm) and their relationship to zircon and the NaTl-type structure
(2011) Schustereit, Tanja; Müller, Sabine L.; Schleid, Thomas; Hartenbach, Ingo
The rare-earth metal(III) ortho-oxomolybdates with the formula Ln0.667[MoO4] (Ln = Ce, Pr, Nd, and Sm) and defect scheelite-type structure crystallize in the tetragonal space group I41/a (a = 533–525, c = 1183–1158 pm) with four formula units per unit cell. The Ln3+ cations at Wyckoff position 4b exhibit a coordination sphere of eight oxygen atoms in the shape of a trigonal dodecahedron. The same site symmetry ( 4 ..) is observed for the tetrahedral oxomolybdate(VI) entities [MoO4]2–, since their central Mo6+ cation is situated at the 4a position. Due to this equal site multiplicity, the lanthanoid(III) cations have to be statistically under-occupied to maintain electroneutrality, thus a defect scheelite structure emerges. The partial structure of both the Ln3+ cations and the [MoO4]2– anions (if shrunk to their centers of gravity) can be best described as distorted diamond-like arrangements. Therefore, these two interpenetrating partial structures exhibit a similar setup as found in the zircon-type as well as in the NaTl-type structure.
Open Access
The defect scheelite-type lanthanum(III) ortho-oxidomolybdate(VI) La0.667[MoO4]
(2013) Schustereit, Tanja; Schleid, Thomas; Hartenbach, Ingo
The crystal structure of La0.667[MoO4] in the Scheelite-type is described in that paper.
Open Access
Hydrothermal synthesis, crystal structure, and spectroscopic properties of pure and Eu3+-doped NaY[SO4]2 ∙ H2O and its anhydrate NaY[SO4]2
(2021) Buyer, Constantin; Enseling, David; Jüstel, Thomas; Schleid, Thomas
The water-soluble colorless compound NaY[SO4]2 ∙ H2O was synthesized with wet methods in a Teflon autoclave by adding a mixture of Na2[SO4] and Y2[SO4]3 ∙ 8 H2O to a small amount of water and heating it up to 190 °C. By slow cooling, single crystals could be obtained and the trigonal crystal structure of NaY[SO4]2 ∙ H2O was refined based on X-ray diffraction data in space group P3221 (a = 682.24(5) pm, c = 1270.65(9) pm, Z = 3). After its thermal decomposition starting at 180 °C, the anhydrate NaY[SO4]2 can be obtained with a monoclinic crystal structure refined from powder X-ray diffraction data in space group P21/m (a = 467.697(5) pm, b = 686.380(6) pm, c = 956.597(9) pm, β = 96.8079(5), Z = 2). Both compounds display unique Y3+-cation sites with eightfold oxygen coordination (d(Y-Os = 220-277 pm)) from tetrahedral [SO4]2− anions (d(S-O = 141-151 pm)) and a ninth oxygen ligand from an H2O molecule (d(Y-Ow = 238 pm) in the hydrate case. In both compounds, the Na+ cations are atoms (d(Na-Os = 224-290 pm) from six independent [SO4]2- tetrahedra each. Thermogravimetry and temperature-dependent PXRD experiments were performed as well as IR and Raman spectroscopic studies. Eu3+-doped samples were investigated for their photoluminescence properties in both cases. The quantum yield of the red luminescence for the anhydrate NaY[SO4]2:Eu3+ was found to be almost 20 times higher than the one of the hydrate NaY[SO4]2 ∙ H2O:Eu3+. The anhydrate NaY[SO4]2:Eu3+ exhibits a decay time of about τ1/e = 2.3 µm almost independent of the temperature between 100 and 500 K, while the CIE1931 color coordinates at x = 0.65 and y = 0.35 are very temperature-consistent too. Due to these findings, the anhydrate is suitable as a red emitter in lighting for emissive displays.
Open Access
Li2Eu3Br2[BO3]2 : a new europium(II) halide oxoborate with yellow luminescence
(2020) Hoslauer, Jean‐Louis; Lissner, Falk; Blaschkowski, Björn; Schleid, Thomas
The europium(II) oxoborate Li2Eu3Br2[BO3]2 featuring lithium and bromide ions was synthesized by the reaction of Eu2O3 with Li[BH4] as lithium‐ and boron‐ as well as EuBr3 as bromide‐source at 750 °C for 24 h in silica‐jacketed sealed niobium capsules. The yellow, air‐stable and yellow fluorescent compound crystallizes in the trigonal space group R3m (a = 1049.06(7) pm, c = 2993.1(3) pm, c/a = 2.853, Z = 12). The two crystallographically distinguishable Eu2+ cations show either an eightfold coordination as bicapped trigonal prism ([EuO6Br2]12-) or a ninefold coordination as monocapped square antiprism ([EuO5Br4]12-). All oxygen atoms stem from isolated triangular [BO3]3- anions and the Li+ cations reside in octahedral voids provided by both oxygen atoms and Br- anions.
Open Access
Li4Ln[PS4]2Cl : chloride-containing lithium thiophosphates with lanthanoid participation (Ln = Pr, Nd and Sm)
(2023) Lange, Pia L.; Bette, Sebastian; Strobel, Sabine; Dinnebier, Robert E.; Schleid, Thomas
The synthesis and structural analysis of three new chloride-containing lithium thiophosphates(V) Li4Ln[PS4]2Cl with trivalent lanthanoids (Ln = Pr, Nd and Sm) are presented and discussed. Single crystals of Li4Sm[PS4]2Cl were obtained and used for crystal structure determination by applying X-ray diffraction. The other compounds were found to crystallize isotypically in the monoclinic space group C2/c. Thus, Li4Sm[PS4]2Cl (a = 2089.31(12) pm, b = 1579.69(9) pm, c = 1309.04(8) pm, β = 109.978(3)°, Z = 12) was used as a representative model to further describe the crystal structure in detail since Li4Pr[PS4]2Cl and Li4Nd[PS4]2Cl were confirmed to be isotypic using powder X-ray diffraction measurements (PXRD). In all cases, a trigonal structure in the space group R3̲ (e.g., a = 1579.67(9) pm, c = 2818.36(16) pm, c/a = 1.784, Z = 18, for Li4Sm[PS4]2Cl) displaying almost identical building units worked initially misleadingly. The structure refinement of Li4Sm[PS4]2Cl revealed bicapped trigonal prisms of sulfur atoms coordinating the two crystallographically distinct (Sm1)3+ and (Sm2)3+ cations, which are further coordinated by four anionic [PS4]3- tetrahedra. The compounds also contain chloride anions residing within channel-like pores made of [PS4]3- units. Eight different sites for Li+ cations were identified with various coordination environments (C.N. = 4-6) with respect to chlorine and sulfur. EDXS measurements supported the stoichiometric formula of Li4Ln[PS4]2Cl, and diffuse reflectance spectroscopy revealed optical band gaps of 2.69 eV, 3.52 eV, and 3.49 eV for Li4Sm[PS4]2Cl, Li4Nd[PS4]2Cl, and Li4Pr[PS4]2Cl, respectively. The activation energy for Li+-cation mobility in Li4Sm[PS4]2Cl was calculated as Ea(Li+) = 0.88 eV using BVEL, which indicates potential as a Li+-cation conductor.
Open Access
Luminescence properties of Y3F[Si3O10]:Ln3+ (Ln = Eu, Tb, Er) with thalenite-type host lattice and crystal structure of Tm3F[Si3O10]
(2023) Schäfer, Marion C.; Petter, Michael; Hartenbach, Ingo; Locke, Ralf J. C.; Zhang, Shuang; Wickleder, Claudia; Schleid, Thomas
With Tm3F[Si3O10], a new representative of the Ln3F[Si3O10] series could be synthesized by the reaction of Tm2O3, TmF3 and SiO2 (molar ratio: 1:1:3), applying an excess of CsBr as a fluxing agent in gas-tightly sealed platinum crucibles for eight days at 750 °C, and designed to yield Tm3F3[Si3O9] or Cs2TmF[Si4O10]. Single crystals of Tm3F[Si3O10] (monoclinic, P21/n; a = 725.04(6), b = 1102.43(9), c = 1032.57(8) pm, β = 97.185(7)°; Z = 4) appear as pale celadon, transparent, air- and water-resistant rhombic plates. According to its thalenite-type structure, Tm3F[Si3O10] contains catena-trisilicate anions [Si3O10]8− and triangular [FTm3]8+ cations. The three crystallographically different Tm3+ cations are coordinated by seven plus one (Tm1) or only seven anions (Tm2 and Tm3) exhibiting a single F- anion for each polyhedron, additional to the majority of O2- anions. Furthermore, the luminescence properties of the isotypic colorless compound Y3F[Si3O10] doped with Eu3+ (red emission), Tb3+ (green emission) and Er3+ (yellow and infrared emission), respectively, are reported in presenting their different excitation and emission spectra.
Open Access
The matlockite-type praseodymium(III) oxide bromide PrOBr
(2011) Talmon-Gros, Pia; Schurz, Christian M.; Schleid, Thomas
The crystal structure of PrOBr is described in this paper.
Open Access
Na3DyCl6
(2011) Schurz, Christian M.; Meyer, Gerd; Schleid, Thomas
In this paper the crystal structure of trisodiumheyachloridodysprosat(III) (cryolite-type structure) is described as well as the method of perparation.
Open Access
New crystal structures of rare‐earth metal(III) oxotellurates(IV) RE2Te3O9: A1‐type (RE=La, Ce) and A2‐type (RE=Pr, Nd)
(2021) Chou, Sheng‐Chun; Höss, Patrick; Russ, Philip L.; Strobel, Sabine; Schleid, Thomas
The new rare-earth metal(III) oxotellurates(IV) RE2Te3O9 (RE=La-Nd) of the so far unknown A-type structure can be obtained as needle-shaped single crystals through solid-state reactions of the corresponding binary oxides. Their crystal structures were determined as A1-type for RE=La and Ce or A2-type for RE=Pr and Nd by single-crystal X-ray diffraction. Both structure types crystallize in the monoclinic crystal system, but in two different non-centrosymmetric space groups: the A1-type with Z=8 in space group P21 (La2Te3O9: a=569.54(3), b=2230.12(13), c=1464.71(4) pm, β=101.205(3)°; Ce2Te3O9: a=567.02(3), b=2222.61(13), c=1457.13(9) pm, β=101.134(3)°) or the A2-type with Z=16 in space group Cc (Pr2Te3O9: a=2838.61(16), b=563.89(3), c=2522.08(15) pm, β=118.816(3)°; Nd2Te3O9: a=2826.38(16), b=561.47(3), c=2511.94(15) pm, β=118.841(3)°). In spite of the differences in the unit-cell parameters and the symmetry, both structures consist of quite similar fundamental building blocks (FBBs) consisting of eight crystallographically distinct rare-earth metal-oxygen polyhedra with C.N.(RE3+) from seven to nine and always twelve different ψ1-tetrahedral oxotellurate(IV) anions [TeO3]2-, which show a high number of secondary bonding interactions (SBIs) with each other in all four cases.
Open Access
On the thermal dimorphy of the strontium perrhenate Sr[ReO4]2
(2024) Conrad, Maurice; Bette, Sebastian; Dinnebier, Robert E.; Schleid, Thomas
Hygroscopic single crystals of a new hexagonal high‐temperature modification of Sr[ReO4]2 were prepared from a melt of Sr[ReO4]2 ⋅ H2O and SrCl2 ⋅ 6 H2O. The structure analysis of the obtained crystals by X‐ray diffraction revealed that the title compound crystallizes in the ThCd[MoO4]3‐type structure with the hexagonal space group P63/m and the lattice parameters a=1023.81(7) pm and c=646.92(4) pm (c/a=0.632) for Z=2 in its quenchable high‐temperature form. Two crystallographically independent Sr2+ cations are coordinated by oxygen atoms forming either octahedra or tricapped trigonal prisms, whereas the Re7+ cations are found in the centers of discrete tetrahedral meta‐perrhenate units [ReO4]-. Temperature‐dependent in‐situ PXRD studies of dry powder samples of Sr[ReO4]2 exhibited its thermal dimorphy with a phase‐transition temperature at 500-550 °C from literature‐known m‐Sr[ReO4]2 into the newly discovered h‐Sr[ReO4]2 (hexagonal).
Open Access
Quaternary selenides EuLnCuSe3 : synthesis, structures, properties and in silico studies
(2022) Grigoriev, Maxim V.; Solovyov, Leonid A.; Ruseikina, Anna V.; Aleksandrovsky, Aleksandr S.; Chernyshev, Vladimir A.; Velikanov, Dmitriy A.; Garmonov, Alexander A.; Molokeev, Maxim S.; Oreshonkov, Aleksandr S.; Shestakov, Nikolay P.; Matigorov, Alexey V.; Volkova, Svetlana S.; Ostapchuk, Evgeniy A.; Kertman, Alexander V.; Schleid, Thomas; Safin, Damir A.
In this work, we report on the synthesis, in-depth crystal structure studies as well as optical and magnetic properties of newly synthesized heterometallic quaternary selenides of the Eu+2Ln+3Cu+1Se3 composition. Crystal structures of the obtained compounds were refined by the derivative difference minimization (DDM) method from the powder X-ray diffraction data. The structures are found to belong to orthorhombic space groups Pnma (structure type Ba2MnS3 for EuLaCuSe3 and structure type Eu2CuS3 for EuLnCuSe3, where Ln = Sm, Gd, Tb, Dy, Ho and Y) and Cmcm (structure type KZrCuS3 for EuLnCuSe3, where Ln = Tm, Yb and Lu). Space groups Pnma and Cmcm were delimited based on the tolerance factor t’, and vibrational spectroscopy additionally confirmed the formation of three structural types. With a decrease in the ionic radius of Ln3+ in the reported structures, the distortion of the (LnCuSe3) layers decreases, and a gradual formation of the more symmetric structure occurs in the sequence Ba2MnS3 → Eu2CuS3 → KZrCuS3. According to magnetic studies, compounds EuLnCuSe3 (Ln = Tb, Dy, Ho and Tm) each exhibit ferrimagnetic properties with transition temperatures ranging from 4.7 to 6.3 K. A negative magnetization effect is observed for compound EuHoCuSe3 at temperatures below 4.8 K. The magnetic properties of the discussed selenides and isostructural sulfides were compared. The direct optical band gaps for EuLnCuSe3, subtracted from the corresponding diffuse reflectance spectra, were found to be 1.87-2.09 eV. Deviation between experimental and calculated band gaps is ascribed to lower d states of Eu2+ in the crystal field of EuLnCuSe3, while anomalous narrowing of the band gap of EuYbCuSe3 is explained by the low-lying charge-transfer state. Ab initio calculations of the crystal structures, elastic properties and phonon spectra of the reported compounds were performed.
Open Access
RbEr2AsS7 : a rubidium-containing erbium sulfide thioarsenate(III) with (S2)2- Ligands According to RbEr2S(S2)[AsS2(S2)]
(2023) Engel, Katja; Schleid, Thomas
The new rubidium-containing erbium sulfide thioarsenate(III) with the structured formula RbEr2S(S2)[AsS2(S2)] was obtained from the syntheses of elemental erbium (Er), arsenic sesquisulfide (As2S3) and rubidium sesquisulfide (Rb2S3) with elemental sulfur (S) at 773 K as transparent, orange, needle-shaped crystals. RbEr2AsS7 crystallizes monoclinically in the space group C2/c with a = 2339.86(12) pm, b = 541.78(3) pm, c = 1686.71(9) pm and β = 93.109(3) ° for Z = 8. The crystal structure features complex [AsS2(S2)]3- anions with two S2- anions and a (S2)2- disulfide dumbbell coordinating end-on as ligands for each As3+ cation. Even outside the ligand sphere of As3+, S2- and (S2)2- can be found as sulfide anions. Two distinct Er3+ cations are surrounded by either nine or seven sulfur atoms. The [ErS9] polyhedra are corner- and face-connected, while the [ErS7] units share common edges, both building chains along [010]. These different chains undergo edge connectivity with each other, resulting in the formation of corrugated layers, which are held together by Rb+ in chains of condensed [RbS9] polyhedra. So, a three-dimensional network is generated, offering empty channels along [010] apt to take up the As3+ lone-pair cations. Wavelength-dispersive X-ray spectroscopy verified a molar Rb:Er:As:S ratio of approximately 1:2:1:7 and diffuse reflectance spectroscopy showed the typical f-f transitions of Er3+, while the optical band gap was found to be 2.42 eV.
Open Access
Scheelite-type sodium neodymium(III) ortho-oxidomolybdate(VI), NaNd[MoO4]2
(2011) Schleid, Thomas; Hartenbach, Ingo
The crystal structure of Scheelite-type NaNd[MoO4]2 is described in the paper.
Open Access
Single crystals of CaNa[ReO4]3 : serendipitous formation and systematic characterization
(2019) Conrad, Maurice; Schleid, Thomas
In an attempt to crystallize Ce[ReO4]4·xH2O from aqueous solutions of equimolar amounts of Ce[SO4]2 and Ba[ReO4]2 via salt‐metathesis the serendipitous formation of colorless, transparent, rod‐shaped single crystals of CaNa[ReO4]3 was observed as a result of calcium and sodium impurities within the improperly deionized water used. Structure analysis by X‐ray diffraction lead to the conclusion that the title compound crystallizes in the ThCd[MoO4]3 structure type with the hexagonal space group P63/m and the lattice parameters a = 991.74(6) pm, c = 636.53(4) pm, c/a = 0.642 for Z = 2. The crystal structure contains purely oxygen surrounded and crystallographically unique cations, namely Ca2+ in tricapped trigonal prismatic (d(Ca-O) = 6 × 249 pm + 3 × 254 pm), Na+ in octahedral (d(Na-O) = 6 × 241 pm), and Re7+ in tetrahedral coordination (d(Re-O) = 171-173 pm). Furthermore, it was possible to yield an almost phase‐pure microcrystalline powder of the title compound from a melt of equimolar amounts of Na[ReO4] and Ca[ReO4]2 stemming from aquatically obtained precursors.