Mixed-metal uranium(VI) iodates: hydrothermal syntheses,structures, and reactivity of Rb[UO(2)(CrO(4))(IO(3))(H(2)O)], A(2)[UO(2)(CrO(4))(IO(3))(2)] (A = K,Rb, Cs), and K(2)[UO(2)(MoO(4))(IO(3))(2)

The reactions of the molecular transition metal iodates A[CrO(3)(IO(3))] (A = K, Rb, Cs) with UO(3) under mild hydrothermal conditions provide access to four new, one-dimensional, uranyl chromatoiodates, Rb[UO(2)(CrO(4))(IO(3))(H(2)O)] (1) and A(2)[UO(2)(CrO(4))(IO(3))(2)] (A = K (2), Rb (3), Cs (4)). Under basic conditions, MoO(3), UO(3), and KIO(4) can be reacted to form K(2)[UO(2)(MoO(4))(IO(3))(2)] (5), which is isostructural with 2 and 3. The structure of 1 consists of one-dimensional[UO(2)(CrO(4))(IO(3))(H(2)O)](-) ribbons that contain uranyl moieties bound by bridging chromate and iodate anions as well as a terminal water molecule to create [UO(7)] pentagonal bipyramidal environments around the U(VI) centers. These ribbons are separated from one another by Rb(+) cations. When the iodate content is increased in the hydrothermal reactions, the terminal water molecule is replaced by a monodentate iodate anion to yield 2-4. These ribbons can be further modified by replacing tetrahedral chromate anions with MoO(4)(2)(-) anions to yield isostructural, one-dimensional [UO(2)(MoO(4))(IO(3))(2)](2)(-) ribbons. Crystallographic data: 1, triclinic, space group P(-)1, a = 7.3133(5) A, b = 8.0561(6) A, c = 8.4870(6) A, alpha = 88.740(1) degrees, beta = 87.075(1) degrees, gamma = 71.672(1) degrees, Z = 2; 2, monoclinic, space group P2(1)/c, a = 11.1337(5) A, b = 7.2884(4) A, c = 15.5661(7) A, beta = 107.977(1) degrees, Z = 4; 3, monoclinic, space group P2(1)/c, a = 11.3463(6) A, b = 7.3263(4) A, c = 15.9332(8) A, beta = 108.173(1) degrees, Z = 4; 4, monoclinic, space group P2(1)/n, a = 7.3929(5) A, b = 8.1346(6) A, c = 22.126(2) A, beta = 90.647(1) degrees, Z = 4; 5, monoclinic, space group P2(1)/c, a = 11.3717(6) A, b = 7.2903(4) A, c = 15.7122(8) A, beta = 108.167(1) degrees, Z = 4.     

Hydrothermal synthesis and structure of a new one-dimensional, mixed-metal U(VI) iodate, Cs(2)[(UO(2))(CrO(4))(IO(3))(2)

The reaction of the molecular transition metal iodate, Cs[CrO(3)(IO(3))], with UO(3) under mild hydrothermal conditions provides access to a new low-dimensional, mixed-metal U(VI) compound, Cs(2)[(UO(2))(CrO(4))(IO(3))(2)] (1). The structure of 1 is quite unusual and consists of one-dimensional (1)(infinity)[(UO(2))(CrO(4))(IO(3))(2)](2-) ribbons separated by Cs(+) cations. These ribbons are formed from [UO(7)] pentagonal bipyramids that contain a uranyl core, [CrO(4)] tetrahedra, and both monodentate and bridging iodate anions. Crystallographic data: 1, monoclinic, space group P2(1)/n, a = 7.3929(5) A, b = 8.1346(6) A, c = 22.126(2) A, beta = 90.647(1) degrees, Z = 4 (T = 193 K).     

Structural polarity induced by cooperative hydrogen bonding and lone-pair alignment in the molecular uranyl iodate Na2[UO2(IO3)4(H2O)

Na2[UO2(IO3)4(H2O)] has been synthesized under mild hydrothermal conditions. Its structure consists of Na+ cations and [UO2(IO3)4(H2O)](2-) anions. The [UO2(IO3)4(H2O)](2-) anions are formed from the coordination of a nearly linear uranyl, UO2(2+), cation by four monodentate IO(3-) anions and a coordinating water molecule to yield a pentagonal bipyramidal environment around the uranium center. The water molecules form intermolecular hydrogen bonds with the terminal oxo atoms of neighboring [UO2(IO3)4(H2O)](2-) anions to yield one-dimensional chains that extend down the b axis. There are two crystallographically unique iodate anions in the structure of Na2[UO2(IO3)4(H2O)]. One of these anions is aligned so that the lone-pair of electrons is also directed along the b axis. The overall structure is therefore polar, owing to the cooperative alignment of both the hydrogen bonds and the lone-pair of electrons on iodate. The polarity of the monoclinic space group C2 (a = 11.3810(12) A, b = 8.0547(8) A, c = 7.6515(8) A, beta = 90.102(2) degrees , Z = 2, T = 193 K) found for this compound is consistent with the structure. Second-harmonic generation of 532 nm light from a 1064 nm laser source yields a response of approximately 16x alpha-SiO2.     

Self-assembly of a polar open-framework uranyl vanadyl hexaoxoiodate(VII) constructed entirely from distorted octahedral building units in the first uranium hexaoxoiodate: K2[(UO2)2(VO)2(IO6)2O].H2O

The reaction of UO(3) with V(2)O(5) and KIO(4) under mild hydrothermal conditions produces K(2)[(UO(2))(2)(VO)(2)(IO(6))(2)O].H(2)O (1) in the form of orange acicular crystals. The structure of 1 consists of UO(6), VO(6), and IO(6) distorted octahedra that are assembled into a polar, open-framework structure. The distorted VO(6) and IO(6) octahedra edge-share to form chains that run down the c-axis. Each VO(6) octahedron also shares a vertex with an adjacent vanadium atom to link the chains together into a ribbon. The IO(6) units also partake in corner-sharing with the UO(6) units to create interconnected elliptical tubes. The major channels in 1 are filled with K(+) cations and water molecules. The polarity of this compound is caused by alignment of distorted vanadyl hexaoxoiodate ribbons and UO(6) trapezoidal bipyramids resulting in a large second-harmonic generation response of 300 times that of alpha-quartz. Crystallographic data: 1, orthorhombic, space group Pba2, a = 9.984(2) A, b = 16.763(3) A, c = 4.977(1) A, Z = 4 (T = 193 K).     

Further evidence for the tetraoxoiodate(V) anion,IO(4)(3-): hydrothermal syntheses and structures of Ba[(MoO(2))(6)(IO(4))(2)O(4)] x H(2)O and Ba(3)[(MoO(2))(2)(IO(6))(2)] x 2H(2)O

The hydrothermal reaction of MoO(3) with BaH(3)IO(6) at 180 degrees C for 3 days results in the formation of Ba[(MoO(2))(6)(IO(4))(2)O(4)] x H(2)O (1). Under similar conditions, the reaction of Ba(OH)(2) x 8H(2)O with MoO(3) and Ba(IO(4))(2) x 6H(2)O yields Ba(3)[(MoO(2))(2)(IO(6))(2)] x 2H(2)O (2). The structure of 1, determined by single-crystal X-ray diffraction, consists of corner- and edge-sharing distorted MoO(6) octahedra that create two-dimensional slabs. Contained within this molybdenum oxide framework are approximately C(2v) tetraoxoiodate(V) anions, IO(4)(3-), that are involved in bonding with five Mo(VI) centers. The two equatorial oxygen atoms of the IO(4)(3-) anion chelate a single Mo(VI) center, whereas the axial atoms are mu(3)-oxo groups and complete the octahedra of four MoO(6) units. The coordination of the tetraoxoiodate(V) anion to these five highly electropositive centers is probably responsible for stabilizing the substantial anionic charge of this anion. The Ba(2+) cations separate the layers from one another and form long ionic contacts with neighboring oxygen atoms and a water molecule. Compound 2 also contains distorted MoO(6) octahedra. However, these solely edge-share with octahedral hexaoxoiodate(VII), IO(6)(5-), anions to form zigzagging one-dimensional, (1)(infinity)[(MoO(2))(IO(6))](3-), chains that are polar. These chains are separated from one another by Ba(2+) cations that are coordinated by additional water molecules. Bond valence sums for the iodine atoms in 1 and 2 are 5.01 and 7.03, respectively. Crystallographic data: 1, monoclinic, space group C2/c, a = 13.584(1) A, b = 7.3977(7) A, c = 20.736(2) A, beta = 108.244(2) degrees, Z = 4; 2, orthorhombic, space group Fdd2, a = 13.356(7) A, b = 45.54(2) A, c = 4.867(3) A, Z = 8.     

Excision of uranium oxide chains and ribbons in the novel one-dimensional uranyl iodates K(2)[(UO(2))3(IO(3))(4)O(2)] and Ba[(UO(2)2(IO(3))(2)O(2)](H(2)O)

The alkali metal and alkaline-earth metal uranyl iodates K(2)[(UO(2))(3)(IO(3))(4)O(2)] and Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) have been prepared from the hydrothermal reactions of KCl or BaCl(2) with UO(3) and I(2)O(5) at 425 and 180 degrees C, respectively. While K(2)[(UO(2))(3)(IO(3))(4)O(2)] can be synthesized under both mild and supercritical conditions, the yield increases from <5% to 73% as the temperature is raised from 180 to 425 degrees C. Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O), however, has only been isolated from reactions performed in the mild temperature regime. Thermal measurements (DSC) indicate that K(2)[(UO(2))(3)(IO(3))(4)O(2)] is more stable than Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) and that both compounds decompose through thermal disproportionation at 579 and 575 degrees C, respectively. The difference in the thermal behavior of these compounds provides a basis for the divergence of their preparation temperatures. The structure of K(2)[(UO(2))(3)(IO(3))(4)O(2)] is composed of [(UO(2))(3)(IO(3))(4)O(2)](2)(-) chains built from the edge-sharing UO(7) pentagonal bipyramids and UO(6) octahedra. Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O) consists of one-dimensional [(UO(2))(2)(IO(3))(2)O(2)](2)(-) ribbons formed from the edge sharing of distorted UO(7) pentagonal bipyramids. In both compounds the iodate groups occur in both bridging and monodentate binding modes and further serve to terminate the edges of the uranium oxide chains. The K(+) or Ba(2+) cations separate the chains or ribbons in these compounds forming bonds with terminal oxygen atoms from the iodate ligands. Crystallographic data: K(2)[(UO(2))(3)(IO(3))(4)O(2)], triclinic, space group P_1, a = 7.0372(5) A, b = 7.7727(5) A, c = 8.9851(6) A, alpha = 93.386(1) degrees, beta = 105.668(1) degrees, gamma = 91.339(1) degrees, Z = 1; Ba[(UO(2))(2)(IO(3))(2)O(2)](H(2)O), monoclinic, space group P2(1)/c, a = 8.062(4) A, b = 6.940(3) A, c = 21.67(1), beta= 98.05(1) degrees, Z = 4.     

Synthesis and characterization of f-element iodate architectures with variable dimensionality, alpha- and beta-Am(IO3)3

Two americium(III) iodates, beta-Am(IO3)3 (I) and alpha-Am(IO3)3 (II), have been prepared from the aqueous reactions of Am(III) with KIO(4) at 180 degrees C and have been characterized by single-crystal X-ray diffraction, diffuse reflectance, and Raman spectroscopy. The alpha-form is consistent with the known structure type I of anhydrous lanthanide iodates. It consists of a three-dimensional network of pyramidal iodate groups bridging [AmO8] polyhedra where each of the americium ions are coordinated to eight iodate ligands. The beta-form reveals a novel architecture that is unknown within the f-element iodate series. beta-Am(IO3)3 exhibits a two-dimensional layered structure with nine-coordinate Am(III) atoms. Three crystallographically unique pyramidal iodate anions link the Am atoms into corrugated sheets that interact with one another through intermolecular IO3-...IO3- interactions forming dimeric I2O10 units. One of these anions utilizes all three O atoms to simultaneously bridge three Am atoms. The other two iodate ligands bridge only two Am atoms and have one terminal O atom. In contrast to alpha-Am(IO3)3, where the [IO3] ligands are solely corner-sharing with [AmO8] polyhedra, a complex arrangement of corner- and edge-sharing mu2- and mu3-[IO3] pyramids can be found in beta-Am(IO3)3. Crystallographic data: I, monoclinic, space group P2(1)/n, a = 8.871(3) A, b = 5.933(2) A, c = 15.315(4) A, beta = 96.948(4) degrees , V = 800.1(4) A(3), Z = 4; II, monoclinic, space group P2(1)/c, a = 7.243(2) A, b = 8.538(3) A, c = 13.513(5) A, beta = 100.123(6) degrees , V = 822.7(5) A(3), Z = 4.     

Intercalation of iodic acid into the layered uranyl iodate, UO2(IO3)2(H2O)

The direct intercalation of iodic acid into the layered uranyl iodate, UO2(IO3)2(H2O), has been observed to yield UO2(IO3)2(H2O).2HIO3 in crystalline form. This is the first example of this type of reaction with iodic acid.     

Synthesis, structure, and spectroscopic properties of Am(IO3)3 and the photoluminescence behavior of Cm(IO3)3

We have prepared Am(IO(3))(3) as a part of our continuing investigations into the chemistry of the 4f- and 5f-elements' iodates. Single crystals were obtained from the reaction of Am(3+) and H(5)IO(6) under mild hydrothermal conditions. Crystallographic data on an eight-day-old crystal are (21 degrees C, Mo Kalpha, lambda = 0.71073 Angstroms): monoclinic, space group P2(1)/c, a = 7.2300(5) Angstroms, b = 8.5511(6) Angstroms, c = 13.5361(10) Angstroms, beta = 100.035(1) degrees, V = 824.06(18), Z = 4. The structure consists of Am(3+) cations bound by iodate anions to form [Am(IO(3))(8)] units, where the local coordination environment around the americium centers is a distorted dodecahedron. There are three crystallographically unique iodate anions within the structure that bridge in both bidentate and tridentate fashions to form the overall three-dimensional structure. Repeated collection of X-ray diffraction data with time for a crystal of (243)Am(IO(3))(3) revealed an anisotropic expansion of the unit cell, presumably from self-irradiation damage, to generate values of a = 7.2159(7) Angstroms, b = 8.5847(8) Angstroms, c = 13.5715(13) Angstroms, beta = 99.492(4) degrees, V = 829.18(23) after approximately five months. The Am(IO(3))(3) crystals have also been characterized by Raman spectroscopy and the spectral results compared to those for Cm(IO(3))(3). Three strong Raman bands were observed for both compounds and correspond to the I-O symmetric stretching of the three crystallographically distinct iodate anions. The Raman profile suggests a lack of interionic vibrational coupling of the I-O stretching, while intraionic coupling provides symmetric and asymmetric components that correspond to each iodate site. Photoluminescence data for both Am(IO(3))(3) and Cm(IO(3))(3) are reported here for the first time. Assignments for the electronic levels of the actinide cations were based on these photoluminescence measurements and indicate the presence of vibronic coupling between electronic transitions and IO(3)(-) vibrational modes in both compounds.     

Cation-cation interactions in neptunyl(V) compounds: hydrothermal preparation and structural characterization of NpO2(IO3) and alpha- and beta-AgNpO2(SeO3)

The hydrothermal reaction of NpO(2) with IO(3)(-) in the presence of nitrate results in the formation of NpO(2)(IO(3)) (1). Under similar conditions, NpO(2) reacts with AgNO(3) and SeO(2) to yield alpha-AgNpO(2)(SeO(3)) (2) and beta-AgNpO(2)(SeO(3)) (3). The structure of 1 consists of distorted pentagonal bipyramidal Np(V) centers that are bridged by iodate anions. In addition, the oxo atoms of the neptunyl(V) cations coordinate adjacent Np(V) centers creating layers that are linked into a three-dimensional network structure by the iodate anions. The structure is polar owing to the alignment of the stereochemically active lone pair of electrons on the iodate anions along the c-axis. alpha-AgNpO(2)(SeO(3)) (2) forms a layered structure consisting of hexagonal bipyramidal NpO(8) polyhedra that are bound by chelating and bridging selenite anions. The primary and secondary structures of 3 are similar to those of 1, and neptunyl-neptunyl interactions are partially responsible for the creation of a three-dimensional network structure. However, the selenite anions in 3 are rotated with respect to the iodate anions found in 1, and the structure is centrosymmetric. The network found in 3 consists of interconnecting, approximately square channels that house the Ag(+) cations. A bond-valance sum parameter of 2.036 A for Np(V) bound exclusively to oxygen has been developed with b = 0.37 A. Crystallographic data: 1, orthorhombic, space group Pna2(1), a = 13.816(2) A, b = 5.8949(8) A, c = 5.5852(8) A, Z = 4; 2, monoclinic, space group P2(1)/n, a = 4.3007(3) A, b = 9.5003(7) A, c = 11.5877(9) A, beta = 95.855(1) degrees, Z = 4; 3, triclinic, space group Ponemacr;, a = 7.1066(6) A, b = 8.3503(7) A, c = 8.3554(7) A, alpha = 89.349(1) degrees, beta = 77.034(1) degrees, gamma = 76.561(1) degrees, Z = 2.     

General route to three-dimensional framework uranyl transition metal phosphates with atypical structural motifs: the case examples of Cs2{(UO2)4[Co(H2O)2]2(HPO4)(PO4)4} and Cs3+x[(UO2)3CuH4-x(PO4)5].H2O

The reaction of UO2(NO3)2.6H2O with Co or Cu metal, phosphoric acid, and CsCl under mild hydrothermal conditions results in the formation of Cs2{(UO2)4[Co(H2O)2(HPO4)(PO4)4} (1) or Cs(3+x)[(UO2)3CuH(4-x)(PO4)5].H2O (2). The structure of 1 contains uranium atoms in pentagonal bipyramidal and hexagonal bipyramidal environments. The interaction of the uranyl cations and phosphate anions creates layers in the [ab] plane. The uranyl phosphate layers are joined together by octahedral Co centers wherein the Co is bound by phosphate and two cis water molecules. In addition, the Co ions are also ligated by a uranyl oxo atom. The presence of these octahedral building units stitches the structure together into a three-dimensional framework where void spaces are filled by Cs+ cations. The structure of 2 contains uranium centers in UO6 tetragonal bipyramidal and UO7 pentagonal bipyramidal geometries. The uranyl moieties are bridged by phosphate anions into sinusoidal sheets that extend into the [bc] plane and are linked into a three-dimensional structure by Cu(II). The Cu centers reside in square planar environments. Charge balance is maintained by Cs+ cations. Both the overall structures and the uranyl phosphate layers in 1 and 2 are novel.     

Synthesis and structure of Ag(6)[(UO(2))(3)O(MoO(4))(5)]: a novel sheet of triuranyl clusters and MoO(4) tetrahedra

The new uranyl molybdate Ag(6)[(UO(2))(3)O(MoO(4))(5)] (1) with an unprecedented uranyl molybdate sheet has been synthesized at 650 degrees C. The structure (monoclinic, C2/c, a = 16.4508(14) A, b = 11.3236(14) A, c = 12.4718(13) A, beta = 100.014(4)(o), V = 2337.4(4) A(3), Z = 4) contains [(UO(2))(3)O(MoO(4))(5)] sheets composed of triuranyl [(UO(2))(3)O] clusters that are connected by MoO(4) tetrahedra. The topology of the uranyl molybdate sheet in 1 represents a major departure from sheets observed in other uranyl compounds. Of the approximately 120 known inorganic uranyl compounds containing sheets of polyhedra, 1 is the only structure that contains trimers of uranyl pentagonal bipyramids that are connected only by the sharing of vertexes with other polyhedra. The sheets are parallel to (001) and are linked by Ag cations.     

Structural and spectroscopic trends in actinyl iodates of uranium,neptunium, and plutonium

Two neptunyl(VI) iodates, NpO(2)(IO(3))(2)(H(2)O) (1) and NpO(2)(IO(3))(2).H(2)O (2), have been prepared from the aqueous reactions of Np(V) in HCl with KIO(4) or H(5)IO(6) at 180 degrees C and have been characterized by single crystal X-ray diffraction and Raman spectroscopy. Both compounds consist of two-dimensional arrangements of pentagonal bipyramidal [NpO(7)] polyhedra with axial neptunyl, NpO(2)(2+), dioxocations. In 1, the neptunium centers are bound in the equatorial plane by four bridging iodate anions and one terminal water molecule. The iodate anions link the [NpO(7)] units into corrugated sheets that interact with one another through intermolecular IO(3)(-)...IO(3)(-) interactions as also observed in UO(2)(IO(3))(2)(H(2)O). Compound 2 is isostructural with the recently reported PuO(2)(IO(3))(2).H(2)O, where oxygen atoms from bridging iodate anions occupy the five equatorial sites around the neptunyl moieties. The iodate anions occur as both mu(2)- and mu(3)-units and link the neptunyl polyhedra into sheets. Both types of iodate anions have their stereochemically active lone-pair of electrons aligned on one side of each layer creating a polar structure. Raman spectra of 1, UO(2)(IO(3))(2)(H(2)O), and PuO(2)(IO(3))(2).H(2)O show a sequential shift of the nu(1)(AnO(2)(2+)) stretch to lower wavenumber as the atomic number of the actinide is increased. Crystallographic data: 1, orthorhombic, space group Pcan, a = 7.684(2) A, b = 8.450(2) A, c = 12.493(3) A, Z = 4; 2, orthorhombic, space group Pna2(1), a = 7.314(1) A, b = 11.631(2) A, c = 9.449(2) A, Z = 4.     

New d0 transition metal iodates: synthesis, structure, and characterization of BaTi(IO3)6, LaTiO(IO3)5, Ba2VO2(IO3)4.(IO3), K2MoO2(IO3)4, and BaMoO2(IO3)4.H2O

Five new d0 transition metal iodates, BaTi(IO3)6, LaTiO(IO3)5, Ba2VO2(IO3)4.(IO3), K2MoO2(IO3)4, and BaMoO2(IO3)4.H2O, have been synthesized by hydrothermal methods using Ba(OH)2.8H2O, La2O3, K2CO3, TiO2, V2O5, MoO3, and HIO3 as reagents. The structures of these compounds were determined by single-crystal X-ray diffraction. All of the reported materials have zero-dimensional or pseudo-one-dimensional crystal structures composed of MO6 (M = Ti4+, V5+, or Mo6+) octahedra connected to IO3 polyhedra. Infrared and Raman spectroscopy, thermogravimetric analysis, and UV-vis diffuse reflectance spectroscopy are also presented. Crystal data: BaTi(IO3)6, trigonal, space group R-3 (No. 148), with a = b = 11.4711(10) A, c = 11.1465(17) A, V = 1270.2(2) A3, and Z = 3; LaTiO(IO3)5, monoclinic, space group P2(1)/n (No. 14), with a = 7.4798(10) A, b = 18.065(2) A, c = 10.4843(14) A, beta = 91.742(2) degrees , V = 1416.0(3) A3, and Z = 4; Ba2VO2(IO3)4.(IO3), monoclinic, space group P2(1)/c (No. 14), with a = 7.5012(9) A, b = 33.032(4) A, c = 7.2150(9) A, beta = 116.612(2) degrees , V = 1598.3(3) A3, and Z = 4; K2MoO2(IO3)4, monoclinic, space group C2/c (No. 15), with a = 12.959(2) A, b = 6.0793(9) A, c = 17.748(3) A, beta = 102.410(4) degrees , V = 1365.5(4) A3, and Z = 4; BaMoO2(IO3)4.H(2)O, monoclinic, space group P2(1)/n (No. 14), with a = 13.3368(17) A, b = 5.6846(7) A, c = 18.405(2) A, beta = 103.636(2) degrees , V = 1356.0(3) A3, and Z = 4.     

Aqueous reactions of U(VI) at high chloride concentrations: syntheses and structures of new uranyl chloride polymers

The reactions of UO(3) with acidic aqueous chloride solutions resulted in the formation of two new polymeric U(VI) compounds. Single crystals of Cs(2)[(UO(2))(3)Cl(2)(IO(3))(OH)O(2)].2H(2)O (1) were formed under hydrothermal conditions with HIO(3) and CsCl, and Li(H(2)O)(2)[(UO(2))(2)Cl(3)(O)(H(2)O)] (2) was obtained from acidic LiCl solutions under ambient temperature and pressure. Both compounds contain pentagonal bipyramidal coordination of the uranyl dication, UO(2)(2+). The structure of 1 consists of infinite [(UO(2))(3)Cl(2)(IO(3))(mu(3)-OH)(mu(3)-O)(2)](2-) ribbons that run down the b axis that are formed from edge-sharing pentagonal bipyramidal [UO(6)Cl] and [UO(5)Cl(2)] units. The Cs(+) cations separate the chains from one another and form long ionic contacts with terminal oxygen atoms from iodate ligands, uranyl oxygen atoms, water molecules, and chloride anions. In 2, edge-sharing [UO(3)Cl(4)] and [UO(5)Cl(2)] units build up tetranuclear [(UO(2))(4)(mu-Cl)(6)(mu(3)-O)(2)(H(2)O)(2)](2-) anions that are bridged by chloride to form one-dimensional chains. These chains are connected in a complex network of hydrogen bonds and interactions of uranyl oxygen atoms with Li(+) cations. Crystal data: 1, orthorhombic, space group Pnma, a = 8.2762(4) A, b = 12.4809(6) A, c = 17.1297(8) A, Z = 4; 2, triclinic, space group P1, a = 8.110(1) A, b = 8.621(1) A, c = 8.740(1) A, Z = 2.     

One- and two-dimensional silver and zinc uranyl phosphates containing bipyridyl ligands

The reaction of AgCN with UO2, 4,4'-bipy, and phosphoric acid in water at 160 degrees C under autogeneously generated pressure results in the formation of [Ag(4,4'-bipy)]2[(UO2)2H3(PO4)3] (AgUP-1). Ag(2,2'-bipy)(UO2)2(HPO4)(PO4) (AgUP-2) has been prepared from the hydrothermal reaction (at 180 degrees C) of KAg(CN)2 with UO2(C2H3O2)2.2H2O and 2,2'-bipy. [Zn(2,2'-bipy)]2[UO2(HPO4)3] (ZnUP-1) was isolated from the hydrothermal reaction of UO2, 2,2'-bipyridyl, Zn(CN)2, and H3PO4. Single crystal X-ray diffraction experiments reveal that the structure of AgUP-1 consists of 2infinity[(UO2)2H3(PO4)3]2- expanded autunite-like layers in the [ac] plane, separated by 1infinity[Ag(4,4'-bipy)]+ chains of two-coordinate Ag+ bridged by 4,4'-bipy. The structure of AgUP-2 is composed of chains of edge-sharing UO7 pentagonal bipyramids that are linked by phosphate anions into 2infinity[(UO2)2(HPO4)(PO4)]1- sheets with the beta-uranophane topology that extend in the [ab] plane. Both sides of the sheets are decorated by [Ag(2,2'-bipy)]+ units, where the Ag+ cations are found in distorted trigonal planar environments. The structure of ZnUP-1 is 1D and consists of UO7 pentagonal bipyramids that are connected by phosphate anions that also bind four-coordinate zinc(II) to the periphery of the chains and five-coordinate zinc within the chains. Intense fluorescence from these compounds was observed.     

Synthesis, crystal structure and optical properties of [Ag(UO2)3(OAc)9][Zn(H2O)4(CH3CH2OH)2]: a novel compound containing closed-shell 3d10, 4d10 and 5d10 metal ions

[Ag(UO(2))(3) (OAc)(9)][Zn(H(2)O)(4)(CH(3)CH(2)OH)(2)] (, OAc = CH(3)COO(-)) crystallized from an ethanol solution and its structure was determined by IR spectroscopy, elemental analysis, (1)H NMR, (13)C NMR and X-ray crystallography; it is composed of [Zn(H(2)O)(4)(CH(3)CH(2)OH)(2)](2+) cations and [Ag(UO(2))(3)(OAc)(9)](2-) anions in which triuranyl [(UO(2))(OAc)(3)](3) clusters are linked by the Ag ion.     

Structural influences of organonitrogen ligands on vanadium oxide solids. Hydrothermal syntheses and structures of the terpyridine vanadates [V2O4(terpy)2]3[V10O28], [VO2(terpy)][V4O10], and [V9O22(terpy)3

Hydrothermal reactions of the V2O5/2,2':6':2"-terpyridine/ZnO/H2O system under a variety of conditions yielded the organic-inorganic hybrid materials [V2O4(terpy)2]3[V10O28].2H2O (VOXI-10), [VO2(terpy)][V4O10] (VOXI-11), and [V9O22(terpy)3] (VOXI-12). The structure of VOXI-10 consists of discrete binuclear cations [V2O4(terpy)2]2+ and one-dimensional chains [V10O28]6-, constructed of cyclic [V4O12]4- clusters linked through (VO4) tetrahedra. In contrast, the structure of VOXI-11 exhibits discrete mononuclear cations [VO2(terpy)]1+ and a two-dimensional vanadium oxide network, [V4O10]1-. The structure of the oxide layer is constructed from ribbons of edge-sharing square pyramids; adjacent ribbons are connected through corner-sharing interactions into the two-dimensional architecture. VOXI-12 is also a network structure; however, in this case the terpy ligand is incorporated into the two-dimensional oxide network whose unique structure is constructed from cyclic [V6O18]6- clusters and linear (V3O5(terpy)3) moieties of corner-sharing vanadium octahedra. The rings form chains through corner-sharing linkages; adjacent chains are connected through the trinuclear units. Crystal data: VOXI-10, C90H70N18O42V16, triclinic P1, a = 12.2071(7) A, b = 13.8855(8) A, 16.9832(10) A, alpha = 69.584(1) degrees, beta = 71.204(1) degrees, gamma = 84.640(1) degrees, Z = 1; VOXI-11, C15H11N3O12V5, monoclinic, P2(1)/n, a = 7.7771(1) A, b = 10.3595(2) A, c = 25.715(4) A, beta = 92.286(1) degrees, Z = 4; VOXI-12, C45H33N9O22V9, monoclinic C2/c, a = 23.774(2) A, b = 9.4309(6) A, c = 25.380(2) A, beta = 112.047(1) degrees, Z = 4.     

Expanding the crystal chemistry of actinyl peroxides: open sheets of uranyl polyhedra in Na5[(UO2)3(O2)4(OH)3](H2O)13

A uranyl peroxide, Na5[(UO2)3(O2)4(OH)3](H2O)13, with an open sheet of uranyl polyhedra has been synthesized under ambient conditions and structurally characterized. The structure (orthorombic, Cmca, a = 23.632(1) A, b = 15.886(1) A, c = 13.952(1) A, V = 5237.7 A(3), and Z = 8) consists of sheets composed of two symmetrically unique uranyl (UO2)2+ ions that are coordinated equatorially by two peroxide groups and two OH(-) groups, forming distorted uranyl hexagonal bipyramids of composition (UO2)(O2)2(OH)2(4-). The uranyl bipyramids are connected into sheets with openings with dimensions 13.7 A along [010] and 15.9 A along [100]. The shortest dimension of the cavity is 8.08 A. Sheets of two-dimensionally polymerized uranyl polyhedra are the most common structural type of inorganic uranyl phases; however, such an open topology has never been observed.     

The structural and spectroscopic characterisation of three actinyl complexes with coordinated and uncoordinated perrhenate: [UO2(ReO4)2(TPPO)3], [[(UO2)(TPPO)3]2(mu2-O2)][ReO4]2 and [NpO2(TPPO)4][ReO4

The first structural characterization of an actinide complex with coordinated perrhenate is reported, [UO2(ReO4)2(TPPO)3] (1). In this [UO2]2+ complex two [ReO4]- anions and three TPPO (triphenylphosphine oxide) P=O donor ligands are coordinated in the equatorial plane in a cisoid arrangement. This bonding arrangement, and apparent strain observed in the equatorially bonded ligands, is attributed to the solid state packing in adjacent molecules in which hydrophobic TPPO ligands form an effective "shell" around a hydrophilic core of two UO2(ReO4)2 moieties. Solid state vibrational spectroscopy (infrared and Raman), 31P CP MAS NMR and elemental analysis are also consistent with the formula of 1. Solution state vibrational spectroscopy and 31P NMR measurements in EtOH indicate the lability of the TPPO and [ReO4]- groups. The photolytic generation of peroxide in EtOH solutions of 1 leads to the formation of trace quantities of [[(UO2)(TPPO)3]2(mu2-O2)][ReO4]2, 2, in which the coordinated [ReO4]- groups of 1 have been displaced by bridging O2(2-), derived from atmospheric O2. Finally, attempts to synthesise a [NpO2]+ analogue of have resulted only in the formation of [NpO2(TPPO)4][ReO4], 3, in which [ReO4]- acts solely as a counter anion. From these results it can be concluded that [ReO4]- will bond to [UO2]2+, but will be readily displaced by a more strongly coordinating ligand (e.g. peroxide) and will not coordinate to an actinyl cation with a lower charge, [NpO2]+, under the same reaction conditions.