The two new copper(II) salts Cu(SeO
4
) and Cu(SeO
3
OH)
2
·6H
2
O were synthesized at low-temperature hydrothermal conditions (220 °C), and room temperature, respectively. Their atomic arrangements ...were studied based on single-crystal X-ray investigations
P
2
1
/
n, a
= 4.823(1),
b
= 8.957(2),
c
= 6.953(1) Å, β = 94.82(1)°, Z = 4;
P
1
¯
,
a
= 6.133(1),
b
= 6.303(1),
c
= 8.648(2) Å, α = 70.45(1), β = 84.60(1), γ = 73.44(1)°, Z = 1. Cu(SeO
4
) adopts the MnAsO
4
structure type. It exhibits structural as well as topological relations with two formerly known isochemical compounds. They crystallize in the structure type ZnSO
4
(mineral name zincosite,
Pnma
) respectively NiSO
4
(
Cmcm
). The two minerals dravertite, CuMg(SO
4
)
2
, and hermannjahnite, CuZn(SO
4
)
2
, are isotypic with CuSeO
4
-
P
2
1
/
n;
interestingly, also α-NaCu(PO
4
) belongs to this structure type: some rotation of the
X
O
4
group allows a supplementary position for the Na atom. — Cu(SeO
3
OH)
2
·6H
2
O represents a new structure type. The protonated selenate group shows an extended Se—O
h
bond distance (1.695 Å) as compared to the other Se—O bonds (1.614 to 1.626 Å). One OH dipole of the three independent H
2
O molecules represents a rather free hydrogen bond. For the other H atoms, the O—H···O lengths vary from 2.585 to 2.799 Å. Interestingly, the distance O
w
7···O
w
7 of only 2.791 Å does not represent an edge in a coordination polyhedron and it is not preliminary involved in the hydrogen bond scheme. All Cu
2+
ions in the two title compounds are in a pronounced 4 + 2 coordination. The Cu
2+4+2
atoms in Cu(SeO
4
) are linked to chains along 100; in Cu(SeO
3
OH)
2
·6H
2
O they are not connected among each other.
The first synthetic pathway using a series of four nonlacunary 4f-heterometal-substituted polyoxotungstate clusters Na21(Ln(H2O)(OH)2(CH3COO))3(WO4)(SbW9O33)3·nH2O (NaLnSbW 9 ; Ln = TbIII, DyIII, ...HoIII, ErIII, YIII) as precursors for the directed preparation of nine new 3d–4f heterometallic tungstoantimonates K5Na12H3TM(H2O)Ln3(H2O)5(W3O11)(SbW9O33)3·nH2O (KTMLnSbW 9 ; TM = CoII, NiII; Ln = TbIII, DyIII, HoIII, ErIII, YIII) has been developed. Systematic studies revealed an increased K content in the aqueous acidic reaction mixture to be the key step in the cation-directed preparation of 3d–4f compounds; among those, the Co-containing members represent the first examples of KCoLnSbW 9 (Ln = TbIII, DyIII, HoIII, ErIII, YIII) heterometallic tungstoantimonates exhibiting the SbW 9 building block. All 13 compounds have been characterized thoroughly in the solid state by powder and single-crystal X-ray diffraction (XRD), revealing a cyclic trimeric polyoxometalate architecture with three SbW 9 units encapsulating a planar triangle of LnIII ions in the case of NaLnSbW 9 and a heterometallic core of one TMII and three LnIII for KTMLnSbW 9 (TM = CoII, NiII; Ln = TbIII, DyIII, HoIII, ErIII, YIII). The results obtained by XRD are supplemented by complementary characterization methods in the solid state such as IR spectroscopy, thermogravimetric analysis, and elemental analysis as well as in solution by UV–vis spectroscopy. Detailed magnetic studies on the representative compounds KTMDySbW 9 (TM = CoII, NiII) and KCoYSbW 9 of the series revealed field-induced slow magnetic relaxation.
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Investigation (electron microprobe and X-ray powder and single crystal diffraction analyses) of the phase relations in the Mn-rich corner (> 45 at% Mn) of the systems Mn-{Ru,Os,Ir}-B, prompted in all ...three systems a ternary compound with formula (Mnx{Ru,Os,Ir}1-x)23B6. For the systems Mn-Ru-B, Mn-Ir-B phase equilibria have been determined at 950°C (Ru), 900°C (Ir) revealing in both cases a small homogeneity region at constant B-content (Mn1-xRux)23B6 (0.29 < x < 0.37); (Mn1-xOsx)23B6 (0.33 < x < 0.37), as well as (Mn1-xIrx)23B6 (0.29 < x < 0.34). The crystal structure of the three compounds was determined from single crystal and X-ray powder intensity data analyses to be isotypic with the Cr23B6-type (so-called tau-phase, space group Fm3¯m, No. 225). In all cases Mn atoms fully occupy the 4a site (0,0,0) at the origin of the unit cell. For the 8c site (¼,¼,¼) we observed a random distribution of Mn1-x(PM)x with decreasing PM content (PM stands for a platinum group metal atom) going from Ru to Os and Ir, where Mn atoms fully occupy 8c. Whereas the remaining sites (48h, 32f) show various ratios of the two metal species, boron atoms fully occupy the centers (24e site) of the Archimedean metal atom antiprisms. A transmission electron microscopic study confirms the absence of superstructures related to these metal atom disorder, thus Mn and PM atoms randomly share their sites. The latter is well reflected in the behavior of the electrical resistivity of these compounds, which is dominated by disorder scattering. For (Mn0.6{Ru,Os}0.4)23B6, temperature dependent dc magnetization studies reveal distinct antiferromagnetic-like anomalies at TN ≅ 72 K and 114 K, respectively. Low field dc and ac magnetic susceptibility data of (Mn0.7Ir0.3)23B6 display a distinct ferromagnetic-like transition at TC = 280 K, consistent with a pronounced specific heat anomaly and a rather continuous temperature dependent evolution of magnetic anisotropy effects. Mechanical properties (hardness) characterize the tau phases among rather hard and brittle intermetallics (about 5–6 GPa).
•Phase relations at ∼900°C in the Mn-corner of the systems Mn-{Ru,Ir}-B.•Single crystal structure analyses (Xray, TEM) of novel Mnx{Ru,Os,Ir}23-xB6.•Tau-borides: Experimental Cp, ρ, χ, ac/dc-magnetization, elastic moduli, HV.•Antiferromagnetic-like anomalies for (Mn0.6{Ru,Os}0.4)23B6 at TN ≅ 72 K, 114 K.•Ferromagnetic-like transition for (Mn0.7Ir0.3)23B6 at TC = 280 K.
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Two new ternary platinum borides, YPtxB6-2x and YbPtxB6-2x, were obtained by argon-arc melting of the elements followed by annealing at 780 °C (750 °C). The structures of these compounds combine the ...fragments of CaB6- and AuCu3-type structures space group Pm3̅m; x = 1.15, a = 4.0550(4) Å and x = 1.34, a = 4.0449(2) Å for YPtxB6-2x and YbPtxB6-2x, respectively; single-crystal X-ray diffraction. Two possible variants of B/Pt ordering (space group P4/mmm) were created via a group-subgroup approach targeting the derived stoichiometry. The architecture of the type-I YPtxB6-2x structure model (a' = a, b' = b, c' = c) combines the 4.82 boron nets alternating with the layers of Y and Pt; the type-II YPtxB6-2x structure model (a' = 2a, b' = 2b, c' = c) exhibits columns of linked B24 truncated cubes filled with Y running along the c axis. The striking features of both structural models are B4Pt2 octahedra. The structural similarities with hitherto reported structures (YB2C2, M2Ni21B20, MNi21B20, and ErNiB4) were drawn supporting the verity of these models. A chemical bonding analysis for type-I and type-II YPtxB6-2x based on electron localization function distribution revealed a two-center interaction forming the 4.82 boron nets for type-I YPtxB6-2x and a covalent bonding within B4Pt2 octahedra as well as a two-center interaction for B-B intraoctahedral bonds for type-II YPtxB6-2x. Analysis of Bader charges revealed the cationic character of the yttrium atoms. The interactions for nondistorted areas of the structures agree well with the bonding picture calculated for constituent building structures, YB6 and YPt3. Electronic structure calculations predict YPtxB6-2x to be a metal with the density of states of around N(EF) = 1 states eV-1 f.u.-1. The exploration of the Y-Pt-B system in the relevant concentration range elucidated the homogeneity field of YPtxB6-2x (0.90 ≤ x ≤ 1.40) and revealed the existence of three more ternary phases at 780 °C: YPt2B (space group P6222), YPt3B (space group P4mm), and YPt5B2 (space group C2/m).
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Two new ternary platinum borides, YPt
B
and YbPt
B
, were obtained by argon-arc melting of the elements followed by annealing at 780 °C (750 °C). The structures of these compounds combine the ...fragments of CaB
- and AuCu
-type structures space group
3̅
;
= 1.15,
= 4.0550(4) Å and
= 1.34,
= 4.0449(2) Å for YPt
B
and YbPt
B
, respectively; single-crystal X-ray diffraction. Two possible variants of B/Pt ordering (space group
4/
) were created via a group-subgroup approach targeting the derived stoichiometry. The architecture of the type-
YPt
B
structure model (
' =
,
' =
,
' =
) combines the 4.8
boron nets alternating with the layers of Y and Pt; the type-
YPt
B
structure model (
' = 2
,
' = 2
,
' =
) exhibits columns of linked B
truncated cubes filled with Y running along the
axis. The striking features of both structural models are B
Pt
octahedra. The structural similarities with hitherto reported structures (YB
C
, M
Ni
B
, MNi
B
, and ErNiB
) were drawn supporting the verity of these models. A chemical bonding analysis for type-
and type-
YPt
B
based on electron localization function distribution revealed a two-center interaction forming the 4.8
boron nets for type-
YPt
B
and a covalent bonding within B
Pt
octahedra as well as a two-center interaction for B-B intraoctahedral bonds for type-
YPt
B
. Analysis of Bader charges revealed the cationic character of the yttrium atoms. The interactions for nondistorted areas of the structures agree well with the bonding picture calculated for constituent building structures, YB
and YPt
. Electronic structure calculations predict YPt
B
to be a metal with the density of states of around
(
) = 1 states eV
f.u.
. The exploration of the Y-Pt-B system in the relevant concentration range elucidated the homogeneity field of YPt
B
(0.90 ≤
≤ 1.40) and revealed the existence of three more ternary phases at 780 °C: YPt
B (space group
6
22), YPt
B (space group
4
), and YPt
B
(space group
2/
).
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The synthesis of Fe(PrIm)6(BF4)2 with the intention of investigating its magnetic and structural properties led to the discovery of a new family of Fe(II) 1‐propyl‐1H‐imidazole complexes, which were ...obtained by simply changing the reaction conditions. The structural, magnetic and electronic properties were investigated.
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The original version of this article unfortunately contained a mistake in Table 3. The corrected Table 3 is given below. The original article has been corrected.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Single‐ and double‐sided functionalized hybrid organic–inorganic Anderson polyoxomolybdates with GaIII and FeIII positioned as central heteroatoms have been synthesized in a mild, two‐step synthesis ...in an aqueous medium. Compounds 1–4 were isolated as hydrated salts, TBA3GaMo6O18(OH)3{(OCH2)3CCH2OH}×12 H2O (1) (TBA=tetrabutylammonium), Na3FeMo6O18{(OCH2)3CCH2OH}2×11 H2O (2), TMA2GaMo6O18(OH)3{(OCH2)3CNH3}×7 H2O (3) (TMA=tetramethylammonium), and NaTMA2FeMo6O18(OH)3{(OCH2)3CNH3}(OH)×6 H2O (4). All the compounds were characterized based on single‐crystal X‐ray diffraction (SXRD), FTIR, UV/Vis, thermogravimetric, ESI‐MS, NMR, and elemental analyses. Compound 1 was also crystallized with two smaller organic cations, giving TMA3GaMo6O18(OH)3{(OCH2)3CCH2OH}×n H2O (5) and GDM3GaMo6O18(OH)3{(OCH2)3CCH2OH}×n H2O (6) (GDM=guanidinium) and were characterized based on UV/Vis, NMR, FTIR, and elemental analyses. The use of these compounds as additives in macromolecular crystallography was investigated by examining their hydrolytic stability by using ESI‐MS in a pH range of 4 to 9. Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) analysis showed that BSA remains intact in a solution containing up to 100 equivalents of 1 or 4 over more than four days at 20 °C. Zeta potential measurements demonstrate that 1–4 induce charge inversions on the positively charged surface of BSA (1 mg mL−1) with concentrations starting as low as 1.29 mM for compounds 1 and 2, which have the highest negative surface charge.
Tailored “biological” POMs: The use of a relatively unexplored, straightforward, and mild procedure leads to the formation of water‐soluble hybrid organic–inorganic Anderson polyoxometalates with different Tris ligands and Ga and Fe as heteroatoms (see figure). All compounds exhibit robust hydrolytic properties and show nonproteolytic electrostatic interactions with BSA and may thus be used as, for example, efficient additives to promote growth of protein crystals.
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