The new compounds
M
2+
Zr(SeO
4
)
3
(
M
2+
= Mg, Mn, Co, Ni, Zn, Cd) and Li
2
Zr(
X
O
4
)
3
(
X
= S, Se) were synthesized at 220 °C by reaction of Zr
2
O
2
(CO
3
)(OH)
2
with hydroxides or ...carbonates of
M
/ Li and the respective acids H
2
SeO
4
/H
2
SO
4
. They form crystals up to several tenths of a mm and were investigated by single crystal X-ray diffraction. The framework structures of these selenates can be deduced from that of monoclinic Fe
2
(SO
4
)
3
in space group
P
2
1
/n
, which is characterized by two types of isolated Fe
3+
O
6
octahedra, corner-linked with three different sulfate groups: ferric iron is substituted in 1:1 ratio by Zr
4+
and
M
2+
as already known for isotypic
M
Zr(SO
4
)
3
representatives. In the case of Li
2
Zr(
X
O
4
)
3
members, one additional lithium atom occupies a tetrahedral vacancy of the Fe
2
(SO
4
)
3
architecture.
Graphical abstract
Recently, we have discovered a new class of amino acids salts containing different amino acids. In the present paper, we report crystal structures of three isostructural salts:
l
-argininium( +) ...sarcosine chloride (I),
l
-argininium( +) sarcosine bromide (II), and
l
-argininium( +) sarcosine iodide (III), formed by slow evaporation at room temperature from aqueous solutions containing stoichiometric ratios of components. The compounds crystallize in the polar space group
P
2
1
with two formula units in the asymmetric unit. The structures are stabilized due to N–H···O and N–H···X (X = Cl, Br, I) hydrogen bonds. Infrared spectra of all three crystals are shown and discussed.
Recently, we have discovered a new class of salts containing different amino acids. In the present paper, we report crystal structures of four types (A(1)HA(2)HY, A(1)HA(2)H···A(2)Y, ...A(1)HA(1)H···A(2)Y and A(1)H···A(2)
2
Y) of salts containing a hexafluorosilicate anion (Y is SiF
6
2−
) and amino acids glycine, sarcosine, dimethylglycine, betaine,
β
-alanine, and
l
-proline: (
β
-AlaH)(BetH)SiF
6
·H
2
O (I), (
β
-AlaH)(
l
-ProH)SiF
6
(II), (
β
-AlaH)(
l
-ProH···
l
-Pro)SiF
6
(III), (BetH)(BetH···Sar)SiF
6
·H
2
O (IV), (GlyH···DMG)
2
SiF
6
(V), and (DMGH···Sar)
2
SiF
6
(VI). The O⋅⋅⋅O distances in dimeric cations (
l
-ProH···
l
-Pro), (BetH···Sar), (GlyH···DMG), and (DMGH···Sar) are 2.439 (3), 2.5310 (12), 2.4979 (9), and 2.4612 (19) Å in (III), (IV), (V), and (VI), respectively.
Zr
2
(OH)
2
(
X
O
4
)
3
·4H
2
O (
X
= S, Se), Zr(SO
4
)
2
·4H
2
O, and Zr(SeO
3
)
2
were synthesized at low-hydrothermal conditions from mixtures of Zr
2
O
2
(CO
3
)(OH)
2
, the respective acids, ...and minor amounts of water. While Zr
2
(OH)
2
(
X
O
4
)
3
·4H
2
O (
X
= S, Se) and Zr(SO
4
)
2
·4H
2
O form crystals up to several tenths of a mm, Zr(SeO
3
)
2
was mainly obtained as microcrystalline powder, single crystals rarely exceeded 10 μm in size. Samples were investigated by single-crystal X-ray techniques and in the case of Zr(SeO
3
)
2
also by X-ray powder diffraction. The compounds Zr
2
(OH)
2
(
X
O
4
)
3
·4H
2
O (
X
= S, Se) crystallize in the Ce
2
(OH)
2
(SO
4
)
3
·4H
2
O structure type (
C
2
/c
,
Z
= 4,
a
= 13.034(2) / 13.308(3),
b
= 6.500(1) / 6.683(2),
c
= 15.056(3) / 15.383(4) Å,
β
= 96.27(1) / 96.81(1)°,
V
= 1267.9(4) / 1358.5(6) Å
3
for
X
= S / Se, respectively). Tetragonal aniprisms Zr
8
O
8
are edge-connected to dimers that share corners with
X
O
4
tetrahedra forming a three-dimensional network. Zr(SO
4
)
2
·4H
2
O (
Fddd
,
Z
= 8,
a
= 5.498(1),
b
= 11.618(3),
c
= 25.893(6) Å,
V
= 1653.9(6) Å
3
) is isotypic with the respective selenate compound. Occasionally, pseudomerohedral twinning is observed, simulating a larger monoclinic
C
-centered unit cell. Again, tetragonal antiprisms Zr
8
O
8
are formed; however, they are corner-linked with SO
4
tetrahedra to Zr(SO
4
)
2
layers interconnected solely by hydrogen bonds. Zr(SeO
3
)
2
crystallizes in
P
2
1
/
c
, Z = 2;
a
= 4.9724(3),
b
= 8.5992(5),
c
= 6.9447(3) Å,
β
= 110.128(3)°,
V
= 278.81(3) Å
3
(unit cell from powder data) and belongs to the β-Sn(SeO
3
)
2
structure type established further for Ti(SeO
3
)
2
and Pb(SeO
3
)
2
. Isolated ZrO
6
octahedra share corners with the selenite groups forming a three-dimensional network.
Graphical abstract
The continuous deposition of hazardous metalliferous wastes derived from industrial steelmaking processes will lead to space shortages while valuable raw metals are being depleted. Currently, these ...landfilled waste products pose a rich resource for microbial thermoacidophilic bioleaching processes. Six thermoacidophilic archaea (
, and
) were cultivated on metal waste product derived from a steelmaking process to assess microbial proliferation and bioleaching potential. While all six strains were capable of growth and bioleaching of different elements,
outperformed other strains and its bioleaching potential was further studied in detail. The ability of
cells to break down and solubilize the mineral matrix of the metal waste product was observed
scanning and transmission electron microscopy. Refinement of bioleaching operation parameters shows that changes in pH influence the solubilization of certain elements, which might be considered for element-specific solubilization processes. Slight temperature shifts did not influence the release of metals from the metal waste product, but an increase in dust load in the bioreactors leads to increased element solubilization. The formation of gypsum crystals in course of
cultivation on dust was observed and clarified using single-crystal X-ray diffraction analysis. The results obtained from this study highlight the importance of thermoacidophilic archaea for future small-scale as well as large-scale bioleaching operations and metal recycling processes in regard to circular economies and waste management. A thorough understanding of the bioleaching performance of thermoacidophilic archaea facilitates further environmental biotechnological advancements.
1‐(3‐Halopropyl)‐1H‐tetrazoles and their corresponding FeII spin‐crossover complexes have been investigated in a combined experimental and theoretical study. Halogen substitution was found to ...positively influence the spin transition, shifting the transition temperature about 70 K towards room temperature. Halogens located at the ω position were found to be too far away from the coordinating tetrazole moiety to have an electronic impact on the spin transition. The subtle variation of the steric demand of the ligand in a highly comparable series was found to have a comparatively large impact on the spin‐transition behavior, which highlights the sensitivity of the effect to subtle structural changes.
Steric fine‐tuning: 1‐(3‐Halopropyl)‐1H‐tetrazoles and their corresponding FeII spin‐crossover complexes have been investigated in a combined experimental and theoretical study. Halogen substitution of 1‐(propyl)‐1H‐tetrazole has been found to shift the spin‐transition temperature by about 70 K towards room temperature (see figure). The reason for this impact was found to lie in the steric fine‐tuning of the ligand backbone.
The title polyoxometalate-based organic–inorganic hybrid compound, Na6(C3H10NO2)4W12O40(OH)2·10H2O, consists of a di-μ3-hydroxido-tetra-μ3-oxido-octadeca-μ-oxido-octadecaoxidododecatungstate ...(paradodecatungstate B) anion, W12O40(OH)210–, and six sodium cations coordinated by the oxygen ions of the polyanions, serinol ligands protonated at the N atom, and water molecules. The centrosymmetric paratungstate B anion shows characteristic features in terms of bond lengths and angles. The three-dimensional framework structure is established by bonding of the sodium cations with oxygen ions of the paratungstate B anions and a network consisting of N—H...O and O—H...O hydrogen bonds of medium strength between the protonated serinol cations, water molecules and the paratungstate B anions. The title compound was also characterized by means of elemental analysis, IR spectroscopy and thermogravimetric analysis.
Stergiouite is a new mineral from the Plaka area in the northern part of the Lavrion Mining District, Greece. The mineral occurs as clusters of stacked, platy crystals, associated with galena, ...sphalerite, native arsenic and sulfur. The crystals are white to colorless, with a pearly luster and white streak. No luminescence under ultraviolet (UV) radiation is observed. Stergiouite is brittle and has a Mohs hardness of ~3. Chemical analysis gave As
2
O
5
42.93 wt%; Sb
2
O
5
2.45 wt%; CaO 10.90 wt%; ZnO 29.79 wt%; and H
2
O
calc
13.93 wt%, which corresponds to an empirical formula Ca
1.02
Zn
1.91
((As
0.95
Sb
0.08
)O
4
)
Σ2.03
· 4H
2
O. The ideal formula is CaZn
2
(AsO
4
)
2
· 4H
2
O. Stergiouite is monoclinic, space group
Pc
, with unit-cell parameters
a
9.416(2) Å;
b
5.300(1) Å;
c
10.893(2) Å;
β
91.767(10)°;
V
543.36(3) Å
3
;
Z
= 2. The strongest lines in the Gandolfi X-ray powder pattern
d
in Å, I/I
100
, (
hkl
) are: 9.406, 100, (100); 4.619, 80, (102), (110); 3.612, 35, (20
2
¯
); 3.494, 35, (112); 2.984, 60, (21
2
¯
); 2.922, 50, (212); 2.720, 20, (004); and 2.647, 25, (020). The crystal structure was refined based on single-crystal X-ray diffraction data to
R
1 = 0.046,
wR
2 = 0.093. The observed mass density of 3.1(2) g cm
−3
compares well with the calculated value (3.183 g cm
−3
). The framework structure of stergiouite is built up by one type of CaO
2
(H
2
O)
4
octahedron and each two ZnO
4
and AsO
4
tetrahedra. These polyhedra share common corners to form three- and four-membered rings. A system of hydrogen bonds (O–O range: 2.70–3.02 Å) further stabilizes the structure. The crystal structure of stergiouite is closely related to that of phosphophyllite Fe
6
Zn
2
4
(PO
4
)
2
· 4H
2
O as well as with members of the hopeite Zn
6
Zn
2
4
(PO
4
)
2
· 4H
2
O group. Stergiouite is named in honour of Vasilis Stergiou (born 1958) in recognition of his contributions to the mineralogy of the Lavrion deposits.
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