The Experts below are selected from a list of 5700 Experts worldwide ranked by ideXlab platform
Hans-conrad Zur Loye - One of the best experts on this subject based on the ideXlab platform.
-
a2mnu3o11 a k rb and li3 2mn1 8u6o22 three new alkali metal manganese uranium vi oxides related to natrotantite
Inorganic Chemistry, 2015Co-Authors: Cory M Read, Mark D Smith, Jeongho Yeon, Gregory Morrison, Hans-conrad Zur LoyeAbstract:Single crystals of three new alkali-metal manganese uranium oxides, K2MnU3O11, Rb2MnU3O11, and Li3.2Mn1.8U6O22, have been grown from molten chloride fluxes and structurally characterized by single-crystal X-ray diffraction. The first two compounds crystallize in the Trigonal Space Group, R3c, in the three-dimensional (3D), natrotantite structure composed of α-U3O8-topological layers connected via MnO6 octahedra. The Li-containing compound crystallizes in the monoclinic Space Group, Cc, with a related 3D structure, composed of β-U3O8-topological sheets connected via irregular MnO7 polyhedra. All three compounds exhibit typical uranyl, UO22+, coordination environments consisting of either UO7 pentagonal bipyramids or UO6 flattened octahedra. The lattice parameters of the new oxides are K2MnU3O11, a = 6.8280(2) A, c = 36.8354(17) A; Rb2MnU3O11, a = 6.8407(2) A, c = 37.5520(17) A; and Li3.2Mn1.8U6O22, a = 11.8958(8) A, b = 10.9639(7) A, c = 13.3269(8) A, and β = 91.442(4)°. The magnetic susceptibilities of t...
-
trivalent cation controlled phase Space of new u iv fluorides na3mu6f30 m al3 ga3 ti3 v3 cr3 fe3 mild hydrothermal synthesis including an in situ reduction step structures optical and magnetic properties
Inorganic Chemistry, 2015Co-Authors: Jeongho Yeon, Mark D Smith, Gregory Morrison, Hans-conrad Zur LoyeAbstract:A series of new, complex U(IV) fluorides, namely, Na3MU6F30 (M = Al3+, Ga3+, Ti3+, V3+, Cr3+, and Fe3+), containing trivalent transition- and main-Group metal cations were synthesized via an in situ reduction step of U(VI) to U(IV). Single crystals of the series were grown in high yield under mild hydrothermal conditions and were characterized by single-crystal X-ray diffraction. The reported compounds crystallize in the Trigonal Space Group P3c1 and exhibit complex crystal structures with a three-dimensional (3-D) framework composed of corner- and edge-shared UF9 polyhedra. The arrangement of U2F16 dimers forms two types of hexagonal channels, where MF6 polyhedra and sodium atoms are located. The most interesting structural feature is the presence of the 3-D framework that can accommodate various transition-metal ions in low oxidation states, indicating that the framework acts as an excellent host. Trivalent transition metal ions, even reduced Ti3+ and V3+, were stabilized by both the rigid framework an...
-
application of a mild hydrothermal approach containing an in situ reduction step to the growth of single crystals of the quaternary u iv containing fluorides na4mu6f30 m mn2 co2 ni2 cu2 and zn2 crystal growth structures and magnetic properties
Journal of the American Chemical Society, 2014Co-Authors: Jeongho Yeon, Mark D Smith, Joshua Tapp, Angela Moller, Hans-conrad Zur LoyeAbstract:A family of rare U(IV)-containing quaternary fluorides, Na4MU6F30 (M = Mn2+, Co2+, Ni2+, Cu2+, and Zn2+), was synthesized in single crystal form via a mild hydrothermal technique utilizing an in situ U(VI) to U(IV) reduction step. The modified hydrothermal route is described, and the conditions to obtain single crystals in high yield are detailed. The crystal structures were determined by single crystal X-ray diffraction. The isostructural fluorides crystallize in a new structure type in the Trigonal Space Group P3c1. They exhibit a complex three-dimensional crystal structure consisting of corner- and edge-shared UF9 and MF6 polyhedra. The main building block, a U6F306– Group, is arranged to create two distinct hexagonal channels, inside which MF6 octahedra and Na+ cations are located. The copper-containing member of the series, Na4CuU6F30, is unusual in that the Cu2+ cation exhibits a rare symmetrical coordination environment consisting of six identical Cu–F bond distances, indicating the lack of the ex...
-
hydroflux crystal growth of platinum Group metal hydroxides sr6napd2 oh 17 li2pt oh 6 na2pt oh 6 sr2pt oh 8 and ba2pt oh 8
Inorganic Chemistry, 2013Co-Authors: Daniel E Bugaris, Mark Smith, Hans-conrad Zur LoyeAbstract:Crystals of five complex metal hydroxides containing platinum Group metals were grown by a novel low-temperature hydroflux technique, a hybrid approach between the aqueous hydrothermal and the molten hydroxide flux techniques. Sr6NaPd2(OH)17 (1) crystallizes in orthorhombic Space Group Pbcn with lattice parameters a = 19.577(4) A, b = 13.521(3) A, and c = 6.885(1) A. This compound has a three-dimensional framework structure with Sr(OH)n polyhedra, Na(OH)6 octahedra, and Pd(OH)4 square planes. Isostructural phases Li2Pt(OH)6 (2) and Na2Pt(OH)6 (3) crystallize in Trigonal Space Group P-3 with lattice parameters of a = 5.3406(8) A and c = 4.5684(9) A and a = 5.7984(8) A and c = 4.6755(9) A, respectively. Structures of these materials consist of layers of A(OH)6 (A = Li (2), Na (3)) and Pt(OH)6 octahedra. Sr2Pt(OH)8 (4) crystallizes in monoclinic Space Group P21/c with lattice parameters a = 5.9717(6) A, b = 10.997(1) A, c = 6.0158(6) A, and β = 113.155(2)°, while Ba2Pt(OH)8 (5) crystallizes in orthorhombic s...
Al Spek - One of the best experts on this subject based on the ideXlab platform.
-
synthesis crystal structure exafs and magnetic properties of catena μ tris 1 2 bis tetrazol 1 yl propane n1 n1 iron ii bis perchlorate first crystal structure of an iron ii spin crossover chain compound
Inorganic Chemistry, 2000Co-Authors: Yann Garcia, Al Spek, O Kahn, L Fournes, H Kooijman, J G Haasnoot, J Moscovici, K Provost, A Michalowicz, Franz RenzAbstract:[Fe(btzp)3](ClO4)2 (btzp = 1,2-bis(tetrazol-1-yl)propane) represents the first structurally characterized Fe(II) linear chain compound exhibiting thermal spin crossover. It shows a very gradual spin transition (T1/2 = 130 K) which has been followed by magnetic susceptibility measurements and 57Fe Mossbauer spectroscopy. The structure has been solved at 200 and 100 K by single-crystal X-ray analysis. It crystallizes in the Trigonal Space Group P3c1 with Z = 2 Fe(II) units at both temperatures. The molecular structure consists of chains running along the c axis in which the Fe(II) ions are linked by three N4,N4‘ coordinating bis(tetrazole) ligands. The main difference between the two forms appears to be in the Fe−N bond lengths, which are 2.164(4) A at 200 K and 2.038(4) A at 100 K. The Fe−Fe separations are 7.422(1) A at 200 K and 7.273(1) A at 100 K. The EXAFS results are consistent with the crystal structure. In both spin states, the FeN6 octahedron is almost regular within the EXAFS resolution. The Fe−...
-
ALKYLATION OF THE S-C-S LINKAGE - TOWARDS LIPOPHILIC MONOTOPIC AND DITOPIC HEAVY-METAL RECEPTORS CONTAINING TRITHIANE BUILDING-BLOCKS - MOLECULAR-STRUCTURE OF CIS-2,4,6-TRIBENZYL-1,3,5-TRITHIANE
1993Co-Authors: Edema Jjh, Franck S. Schoonbeek, Hoogenraad M, Rm Kellogg, Kooijman H, Al SpekAbstract:Reaction of 1,3,5-trithiane with BuLi in THF at - 50-degrees-C, followed by reaction with an equivalent amount of alkyl halide [n-hexyl (a), benzyl (b), n-dodecyl (c)] affords the corresponding lipophilic alkyl trithianes in moderate to good yields (25-75%). Reactions with xylylene dibromides (ortho, meta, para) proceeded analogously to afford potentially ditopic ligands in reasonable overall yields (30-50%). Alkylation of 1,3,5-trithiane with excess alkyl halide results in the stereoselective formation of all-cis di- or trisubstituted trithianes. Investigation of the complexation behavior of these alkylated trithianes with Ag+ was done by means of conductometric titrations of AgO3SCF3 in MeCN and THF. The molecular structure of 2,4,6-tribenzyl-1,3,5-trithiane (4b) has been determined by X-ray crystallography. Crystal data for 4b: Trigonal, Space Group R-3 with a = b = 13.2287(7), c = 20.9177(2) angstrom, Z = 6, R = 0.030 (R(w) = 0.034) for 1564 reflections
Kang Min Ok - One of the best experts on this subject based on the ideXlab platform.
-
cation size effect on the framework structures in a series of new alkali metal indium selenites ain seo3 2 a na k rb and cs
Inorganic Chemistry, 2012Co-Authors: Kang Min OkAbstract:: A new family of quaternary alkali-metal indium selenites, AIn(SeO(3))(2) (A = Na, K, Rb, and Cs) have been synthesized, as crystals and pure polycrystalline phases through standard solid-state and hydrothermal reactions. The structures of the reported materials have been determined by single-crystal X-ray diffraction. While AIn(SeO(3))(2) (A = Na, K, and Rb) crystallize in the orthorhombic Space Group, Pnma, with three-dimensional framework structures, CsIn(SeO(3))(2) crystallizes in the Trigonal Space Group, R3m, with a two-dimensional structure. All of the reported materials, however, share a common structural motif, a network of corner-shared InO(6) octahedra and SeO(3) Groups. Interestingly, the size of the alkali-metal cations profoundly influences the bonding nature of the SeO(3) Group to the InO(6) octahedra. Complete characterizations including infrared spectroscopy, elemental analyses, and thermal analyses for the compounds are also presented, as are dipole moment calculations. A detailed cation size effect on the framework structure is discussed.
Jeongho Yeon - One of the best experts on this subject based on the ideXlab platform.
-
a2mnu3o11 a k rb and li3 2mn1 8u6o22 three new alkali metal manganese uranium vi oxides related to natrotantite
Inorganic Chemistry, 2015Co-Authors: Cory M Read, Mark D Smith, Jeongho Yeon, Gregory Morrison, Hans-conrad Zur LoyeAbstract:Single crystals of three new alkali-metal manganese uranium oxides, K2MnU3O11, Rb2MnU3O11, and Li3.2Mn1.8U6O22, have been grown from molten chloride fluxes and structurally characterized by single-crystal X-ray diffraction. The first two compounds crystallize in the Trigonal Space Group, R3c, in the three-dimensional (3D), natrotantite structure composed of α-U3O8-topological layers connected via MnO6 octahedra. The Li-containing compound crystallizes in the monoclinic Space Group, Cc, with a related 3D structure, composed of β-U3O8-topological sheets connected via irregular MnO7 polyhedra. All three compounds exhibit typical uranyl, UO22+, coordination environments consisting of either UO7 pentagonal bipyramids or UO6 flattened octahedra. The lattice parameters of the new oxides are K2MnU3O11, a = 6.8280(2) A, c = 36.8354(17) A; Rb2MnU3O11, a = 6.8407(2) A, c = 37.5520(17) A; and Li3.2Mn1.8U6O22, a = 11.8958(8) A, b = 10.9639(7) A, c = 13.3269(8) A, and β = 91.442(4)°. The magnetic susceptibilities of t...
-
trivalent cation controlled phase Space of new u iv fluorides na3mu6f30 m al3 ga3 ti3 v3 cr3 fe3 mild hydrothermal synthesis including an in situ reduction step structures optical and magnetic properties
Inorganic Chemistry, 2015Co-Authors: Jeongho Yeon, Mark D Smith, Gregory Morrison, Hans-conrad Zur LoyeAbstract:A series of new, complex U(IV) fluorides, namely, Na3MU6F30 (M = Al3+, Ga3+, Ti3+, V3+, Cr3+, and Fe3+), containing trivalent transition- and main-Group metal cations were synthesized via an in situ reduction step of U(VI) to U(IV). Single crystals of the series were grown in high yield under mild hydrothermal conditions and were characterized by single-crystal X-ray diffraction. The reported compounds crystallize in the Trigonal Space Group P3c1 and exhibit complex crystal structures with a three-dimensional (3-D) framework composed of corner- and edge-shared UF9 polyhedra. The arrangement of U2F16 dimers forms two types of hexagonal channels, where MF6 polyhedra and sodium atoms are located. The most interesting structural feature is the presence of the 3-D framework that can accommodate various transition-metal ions in low oxidation states, indicating that the framework acts as an excellent host. Trivalent transition metal ions, even reduced Ti3+ and V3+, were stabilized by both the rigid framework an...
-
application of a mild hydrothermal approach containing an in situ reduction step to the growth of single crystals of the quaternary u iv containing fluorides na4mu6f30 m mn2 co2 ni2 cu2 and zn2 crystal growth structures and magnetic properties
Journal of the American Chemical Society, 2014Co-Authors: Jeongho Yeon, Mark D Smith, Joshua Tapp, Angela Moller, Hans-conrad Zur LoyeAbstract:A family of rare U(IV)-containing quaternary fluorides, Na4MU6F30 (M = Mn2+, Co2+, Ni2+, Cu2+, and Zn2+), was synthesized in single crystal form via a mild hydrothermal technique utilizing an in situ U(VI) to U(IV) reduction step. The modified hydrothermal route is described, and the conditions to obtain single crystals in high yield are detailed. The crystal structures were determined by single crystal X-ray diffraction. The isostructural fluorides crystallize in a new structure type in the Trigonal Space Group P3c1. They exhibit a complex three-dimensional crystal structure consisting of corner- and edge-shared UF9 and MF6 polyhedra. The main building block, a U6F306– Group, is arranged to create two distinct hexagonal channels, inside which MF6 octahedra and Na+ cations are located. The copper-containing member of the series, Na4CuU6F30, is unusual in that the Cu2+ cation exhibits a rare symmetrical coordination environment consisting of six identical Cu–F bond distances, indicating the lack of the ex...
Suchithra Ashoka Sahadevan - One of the best experts on this subject based on the ideXlab platform.
-
conducting anilate based mixed valence fe ii fe iii coordination polymer small polaron hopping model for oxalate type fe ii fe iii 2d networks
Journal of the American Chemical Society, 2018Co-Authors: Suchithra Ashoka Sahadevan, Alexandre Abherve, Noemi Monni, Cristina Saenz De Pipaon, Jose Ramon Galanmascaros, J C Waerenborgh, Bruno J C Vieira, Pascale Aubansenzier, Sebastien PilletAbstract:The mixed-valence FeIIFeIII 2D coordination polymer formulated as [TAG][FeIIFeIII(ClCNAn)3]·(solvate) 1 (TAG = tris(amino)-guanidinium, ClCNAn2– = chlorocyanoanilate dianionic ligand) crystallized in the polar Trigonal Space Group P3. In the solid-state structure, determined both at 150 and at 10 K, anionic 2D honeycomb layers [FeIIFeIII(ClCNAn)3]− establish in the ab plane, with an intralayer metal–metal distance of 7.860 A, alternating with cationic layers of TAG. The similar Fe–O distances suggest electron delocalization and an average oxidation state of +2.5 for each Fe center. The cation imposes its C3 symmetry to the structure and engages in intermolecular N–H···Cl hydrogen bonding with the ligand. Magnetic susceptibility characterization indicates magnetic ordering below 4 K and the presence of a hysteresis loop at 2 K with a coercive field of 60 Oe. Mossbauer measurements are in agreement with the existence of Fe(+2.5) ions at RT and statistic charge localization at 10 K. The compound shows semico...
