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1.
Inorg Chem ; 55(23): 12185-12192, 2016 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-27934437

RESUMO

A new strontium uranyl oxyfluoride, [(UO2)4F13][Sr3(H2O)8](NO3)·H2O, was synthesized under hydrothermal conditions. The single-crystal X-ray structure was determined. This compound crystallizes in the triclinic space group P1̅ (No. 2), with unit cell parameters a = 10.7925(16) Å, b = 10.9183(16) Å, c = 13.231(2) Å, α = 92.570(8)°, ß = 109.147(8)°, γ = 92.778(8)°, V = 1468.1(4) Å3, and Z = 2. The structure is built from uranyl-containing [Formula: see text] chains of tetrameric units of corner-sharing UO2F5 pentagonal bipyramids. These chains are linked through trimeric strontium units to form strontium-uranyl oxyfluoride layers further assembled by nitrate groups. The interlayer space is occupied by free water molecules. This compound was characterized by spectroscopic methods, especially 19F NMR highlighting the many different fluoride sites. Structural relationships with other uranyl oxyfluorides were investigated through the different F/O ratios, the structural building unit, and the structural arrangement.

2.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 1): m12-3, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23476315

RESUMO

In the title hydrated mol-ecular salt, [Fe(C12H8N2)3](C9H5N4O)2·0.5H2O, the water mol-ecule site is half-occupied. The Fe-N bond lengths within the octa-hedral tris-chelate [Fe(phen)3](2+) ion (phen is 1,10-phenantroline) are indicative of a low-spin d(6) electronic configuration for the metal ion. The C-N, C-C and C-O bond lengths in the polynitrile anions indicate extensive electronic delocalization. In the crystal, the components are linked through O-H⋯N hydrogen bonds, forming [100] chains, as well as through Coulombic inter-actions.

3.
Acta Crystallogr Sect E Struct Rep Online ; 69(Pt 6): m335-6, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23794997

RESUMO

In the monomeric title complex, [Co(C6H8O4)(C10H9N3)(H2O)2]·3H2O, the distorted octa-hedral CoN2O4 coordination environment comprises two N-atom donors from the bidentate di-pyridyldi-amine ligand, two O-atom donors from one of the carboxyl-ate groups of the bidentate chelating adipate ligand and two water mol-ecules. In addition, there are three solvent water mol-ecules which are involved in both intra- and inter-unit O-H⋯O hydrogen-bonding inter-actions, which together with an amine-water N-H⋯O hydrogen bond produce a three-dimensional framework.

4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): i23, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589749

RESUMO

Single crystals of Ca(5)Zr(3)F(22), penta-calcium trizirconium docosafluoride, were obtained unexpectedly by solid-state reaction between CaF(2) and ZrF(4) in the presence of AgF. The structure of the title compound is isotypic with that of Sr(5)Zr(3)F(22) and can be described as being composed of layers with composition [Zr(3)F(20)](8-) made up from two different [ZrF(8)](4-) square anti-prisms (one with site symmetry 2) by corner-sharing. The layers extending parallel to the (001) plane are further linked by Ca(2+) cations, forming a three-dimensional network. Amongst the four crystallographically different Ca(2+) ions, three are located on twofold rotation axes. The Ca(2+) ions exhibit coordination numbers ranging from 8 to 12, depending on the cut off, with very distorted fluorine environments. Two of the Ca(2+) ions occupy inter-stices between the layers whereas the other two are located in void spaces of the [Zr(3)F(20)](8-) layer and alternate with the two Zr atoms along [010]. The crystal under investigation was an inversion twin.

5.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 7): m900-1, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-22807741

RESUMO

In the structure of the title compound, (C5H7N2)[Cr(C2O4)2(H2O)2], two crystallographically independent formula units are present. Both chromium atoms are six-coordinated in a distorted octa-hedral geometry by two chelating equatorial oxalato ligands and two axial water mol-ecules. The [Cr(C2O4)2(H2O)2]⁻ anions and C5H7N2 ⁺ cations are linked through a complex three-dimensional hydrogen-bonding network consisting of N-H⋯O and O-H⋯O inter-actions.

6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 3): o615, 2011 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-21522372

RESUMO

The title compound, C(16)H(24)Cl(2)O, was synthesized from ß-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzocyclo-heptene), which was isolated from essential oil of the Atlas cedar (Cedrus atlantica). The two fused rings exhibit different conformations: the six-membered ring has a screw-boat conformation, while the seven-membered ring displays a boat conformation. The dihedral angle between the two rings is 56.56 (18)°. In the crystal, mol-ecules aggregate into supra-molecular chains along the c axis mediated by O-H⋯O hydrogen bonds.

7.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 3): o645-6, 2011 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-21522398

RESUMO

The title compound, C(16)H(23)Cl(2)NO, was synthesised from ß-himachalene (3,5,5,9-tetra-methyl-2,4a,5,6,7,8-hexa-hydro-1H-benzocyclo-heptene), which was isolated from the essential oil of the Atlas cedar (Cedrus Atlantica). The mol-ecule contains a seven membered ring, which is fused to a five- and a three-membered ring. The five-membered ring has a twisted conformation, whereas the seven-membered ring displays a chair conformation. The dihedral angle between the five- and seven-membered rings is 45.26 (9)°. The absolute structure was established unambiguously from anomalous dispersion effects. In the crystal, mol-ecules are linked into chains propagating along the b axis by inter-molecular N-H⋯O hydrogen bonds; an intramolecular N-H⋯O link also occurs.

8.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): o1818, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21837187

RESUMO

The title compound, C(15)H(15)NO, which was synthesized under solvent-free conditions by the reaction of acetoacetone and 2-naphthyl-amine, adopts a Z conformation about the C=C bond. The enamine-ketone fragment is approximately planar [maximum deviation = 0.026 (3) Å] and forms a dihedral angle of 39.78 (3)° with the naphthalene ring system. An intra-molecular N-H⋯O hydrogen bond is observed.

9.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 6): o1358, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754752

RESUMO

The title compound, C(21)H(25)ClO, was semi-synthesized from isocostic acid, isolated from the aerial part of Inula Viscosa- (L) Aiton [or Dittrichia Viscosa- (L) Greuter]. The cyclo-hexene ring has a half-chair conformation, whereas the cyclo-hexane ring displays a chair conformation.

10.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 6): o1381, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754771

RESUMO

The title compound, C(22)H(28)O, was isolated from the aerial part of Inula viscosa- (L) Aiton [or Dittrichia viscosa- (L) Greuter]. The cyclo-hexene ring has a half-chair conformation, whereas the cyclo-hexane ring displays a chair conformation being substituted at position 2 by a 3-(4-methyl-phen-yl)prop-2-enoyl group. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link mol-ecules into chains in the [010] direction.

11.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 6): o1388-9, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21754777

RESUMO

The title compound, C(21)H(27)NO(4), was synthesized from 9α-hy-droxy-parthenolide, which was isolated from the chloro-form extract of the aerial parts of Anvillea radiata. The asymmetric unit contains two independent mol-ecules. In each, the ten-membered ring displays an approximative chair-chair conformation. Each of the five-membered rings adopts a flattened envelope conformation, the C(H)-C-C(H) atoms representing the flap lie out of the mean plane through the remaining four atoms by 0.443 (2) and 0.553 (2) Å. The dihedral angle between the least-squares planes through the ten- and five-membered rings in the two mol-ecules are similar [22.54 (17) and 23.39 (14)°]. In the crystal, mol-ecules are linked by O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds.

12.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): o1842-3, 2011 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21837209

RESUMO

The title compound, C(19)H(29)NO(5), was synthesized from 9α-hy-droxy-parthenolide (9α-hy-droxy-4,8-dimethyl-12-methyl-ene-3,14-dioxatricyclo-[9.3.0.0(2,4)]tetra-dec-7-en-13-one), which was isolated from the chloro-form extract of the aerial parts of Anvillea radiata. The mol-ecule is built up from two fused five- and ten-membered rings with the (pyrrolidin-4-yl)methyl group as a substituent. The two five-membered ring display the same envelope conformations, whereas the ten-membered ring adopts an approximate chair-chair conformation. The dihedral angle between the ten-membered ring and the lactone ring is 21.81 (9)°. An intra-molecular O-H⋯N hydrogen bond stabilizes the mol-ecular conformation. In the crystal, inter-molecular C-H⋯O inter-actions link the mol-ecules into chains parallel to the c axis.

13.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 9): o2226-7, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22065010

RESUMO

The title compound, C(19)H(29)O(4), was synthesized from 9α-hy-droxy-parthenolide (9α-hy-droxy-4,8-dimethyl-12-methylen-3,14-dioxatricyclo-[9.3.0.0(2,4)]tetra-dec-7-en-13-one), which was isolated from the chloro-form extract of the aerial parts of Anvillea radiata. The mol-ecule is built up from two fused five- and ten-membered rings with the pyrrolidin-1-ylmethyl group as a substituent. The five-membered lactone ring has an envelope conformation, whereas the ten-membered and pyrrolidine rings display approximate chair-chair and twisted conformations, respectively. The dihedral angle between the ten-membered ring and the lactone ring is 18.01 (19)°. An intra-molecular O-H⋯N hydrogen bond occurs. The crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen-bonding inter-actions.

14.
Inorg Chem ; 49(2): 686-94, 2010 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-20020730

RESUMO

The crystal structure of the new Li(5.5)Ce(12)F(50) compound has been fully characterized by single-crystal and synchrotron powder X-ray diffraction. An accurate pseudotetragonal structure was described in the monoclinic P2(1) space group with 68 independent crystallographic sites. The Li(5.5)Ce(12)F(50) composition belongs to the Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50) solid solution. Its structure consists of an opened fluorine framework where a channel network allows the intercalation of relatively mobile lithium cations, inducing the formation of the mixed-valence cerium (the intercalation of Li(+) leads to the reduction of a part of Ce(4+) to Ce(3+)). One part of the lithium ions, necessary for the electroneutrality of the tetravalent equivalent cerium fluoride (Li(2)Ce(12)F(50) composition), is in a locked fluorine polyhedron. Only the supplementary x amount of lithium is able to be exchanged in Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50). The structure of Li(2+x)Ce(x)(3+)Ce(12-x)(4+)F(50) is a rearrangement, due to lithium intercalation, of the base CeF(4) structure. Bond valence calculation on Ce sites, Ce coordination polyhedra volumes, and a calculated Ce cationic radius give the indication of a partial long-range ordering of trivalent and tetravalent cerium cations in specific slabs of the structure. (7)Li NMR spectroscopy and XPS analyses have confirmed all of the structure details.

15.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 6): i46, 2010 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-21579264

RESUMO

Single crystals of the title compound, tetra-lutetium(III) tris-(cyclo-tetra-phosphate), Lu(4)(P(4)O(12))(3), were obtained by solid-state reaction. The cubic structure is isotypic with its Al(III) and Sc(III) analogues and is built up from four-membered (P(4)O(12))(4-) phosphate ring anions ( symmetry), isolated from each other and further linked through isolated LuO(6) octa-hedra (.3. symmetry) via corner sharing. Each LuO(6) octa-hedron is linked to six (P(4)O(12))(4-) rings, while each (P(4)O(12))(4-) ring is linked to eight LuO(6) octa-hedra.

16.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 7): i49-i50, 2010 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-21587666

RESUMO

Single crystals of the title compound, K(2)Al(2)P(8)O(24), were obtained by solid-state reaction. The monoclinic structure is isotypic with that of the Ga(III) analogue and is built of eight-membered phosphate ring anions P(8)O(24) (8-) (2/m symmetry) isolated from each other and further linked by isolated AlO(6) octa-hedra ( symmetry) by sharing corners. Each AlO(6) octa-hedron is linked to four P(8)O(24) (8-) rings in such a way that two rings are linked through bidentate diphosphate groups attached in the cis positions on two opposite parallel edges of the octa-hedron. The two other rings are linked via corner-sharing to the two remaining corners in the trans positions of the AlO(6) octa-hedron. Each P(8)O(24) (8-) ring anion is linked to eight AlO(6) octa-hedra. More accurately, each ring anion is linked to four AlO(6) octa-hedra through bidentate diphosphate groups attached in the cis positions to the AlO(6) octa-hedron and to the four remaining octa-hedra by sharing corners. This three-dimensional linkage delimits channels running parallel to [001] in which the ten-coordinated K(+) cations (2 symmetry) are distributed over two columns. These columns alternate with empty octa-gonally-shaped channels expanding through the P(8)O(24) (8-) ring anions.

17.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 1): i6-i7, 2010 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-21522514

RESUMO

Single crystals of the title compound, K(2)[Ni(H(2)O)(6)][ZrF(6)](2), were grown by slow evaporation of a 40% aqueous HF solution in which a stoichiometric mixture of NiCl(2)·6H(2)O, ZrF(4) and KCl was dissolved. The monoclinic structure is isotypic with its K(2)Cu, K(2)Zn, Cs(2)Zn and Cs(2)Cu analogues. The structure is built up from isolated, slightly elongated octa-hedral [Ni(H(2)O)(6)](2+) complex cations (symmetry ) and dimeric [Zr(2)F(12)](4-) complex anions (symmetry ) that are also isolated from each other. The [Zr(2)F(12)](4-) anion results from the association of two distorted penta-gonal-bipyramidal [ZrF(7)] coordination polyhedra by sharing an equatorial edge passing through an inversion center of the unit cell. Both isolated [Ni(H(2)O)(6)](2+) and [Zr(2)F(12)](4-) complex ions are situated in planes parallel to (010). They are connected by the eight-coordinated K(+) ions into a three-dimensional structure. An intricate O-H⋯F hydrogen-bonding network consolidates the structure.

18.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 3): i17, 2010 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-21580196

RESUMO

Single crystals of the title compound, Al(2)P(6)O(18), were obtained by solid-state reaction. The monoclinic structure is isotypic with its Cr(III), Ga(III) and Ru(III) analogues and is built up of six-membered phosphate ring anions, P(6)O(18) (6-), isolated from each other and further linked by isolated AlO(6) octa-hedra by sharing corners. Each AlO(6) octa-hedron is linked to four P(6)O(18) (6-) rings. More accurately, two rings are linked through bidentate diphosphate groups attached in the cis-positions to the AlO(6) octa-hedron. The other two rings are linked to the two remaining corners, also in cis-positions of the AlO(6) octa-hedron.

19.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 4): i28-i29, 2010 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-21580462

RESUMO

Single crystals of the title compound, NaTb(PO(3))(4), were obtained by solid-state reaction. This compound belongs to type II of long-chain polyphosphates with the general formula A(I)B(III)(PO(3))(4). It is isotypic with the NaNd(PO(3))(4) and NaEr(PO(3))(4) homologues. The crystal structure is built up of infinite crenelated chains of corner-sharing PO(4) tetra-hedra with a repeating unit of four tetra-hedra. These chains, extending parallel to [100], are linked by isolated TbO(8) square anti-prisms, forming a three-dimensional framework. The Na(+) ions are located in channels running along [010] and are surrounded by six oxygen atoms in a distorted octa-hedral environment within a cut-off distance <2.9 Å.

20.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 8): i59-i60, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-21588081

RESUMO

Single crystals of the title compound, potassium praseodymium(III) polyphosphate, were obtained by solid-state reaction. The monoclinic non-centrosymmetric structure is isotypic with all other KLn(PO(3))(4) analogues from Ln = La to Er, inclusive. The crystal structure of these long-chain polyphosphates is built up from infinite crenelated polyphosphate chains of corner-sharing PO(4) tetra-hedra with a repeating unit of four tetra-hedra. These chains, running along [100], are arranged in a pseudo-tetra-gonal rod packing and are further linked by isolated PrO(8) square anti-prisms [Pr-O = 2.3787 (9)-2.5091 (8) Å], forming a three-dimensional framework. The K(+) ions reside in channels parallel to [010] and exhibit a highly distorted coordination sphere by eight O atoms at distances ranging from 2.7908 (9) to 3.1924 (11) Å.

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