13813-22-4Relevant academic research and scientific papers
The first reduced rare earth halide with a group 11 element as interstitial: La3I3Au
Mattausch, Hansjuergen,Zheng, Chong,Kienle, Lorenz,Simon, Arndt
, p. 2367 - 2372 (2004)
The title compound was synthesized from La, LaI3 and Au under Ar atmosphere in the temperature range 850-950°C. It crystallizes in the cubic space group I4132 with lattice constant a = 12.661(2) A. The structure features Au-centered helical octahedron chains arranged in all three directions with 90 degree turns. It is the first reduced rare earth halide with a group 11 interstitial. It is very air and moisture sensitive, and produces crimson-colored Au precipitate similar to Gold Purple of Cassius upon reaction with water or ethanol.
Rare earth halides Ln4X5Z. Part 1: C and/or C 2 in Ln4X5Z
Mattausch, Hansjuergen,Schaloske, Manuel C.,Hoch, Constantin,Zheng, Chong,Simon, Arndt
, p. 491 - 497 (2008)
The compounds Ln4X5Cn (Ln = La, Ce, Pr; X = Br, I and 1.0 3, Ln metal and graphite in sealed Ta-ampoules at temperatures 850 °C 4I5C1.5: a = 19.849(4) A, b = 4.1410(8) A, c = 8.956(2) A, β = 103.86(3)°, La 4I5C2.0: a = 19.907(4) A, b = 4.1482(8) A, c = 8.963(2) A, β = 104.36(3)°, Ce4 Br 5C1.0: a = 18.306(5) A, b = 3.9735(6) A, c = 8.378(2) A, β=104.91(2)°, Ce4Br5C 1.5: a = 18.996(2) A, b = 3.9310(3)A, c = 8.282(7) A, β = 106.74(1)°, Pr4 Br5C1.3: a = 18.467(2) A, b = 3.911(1) A, c = 8.258(7) A, β = 105.25(1)° and Pr4Br5C1.5: a = 19.044(2) A, b = 3.9368(1) A, c = 8.254(7) A, β = 106.48(1)°. In the crystal structure the lanthanide metals are connected to Ln 6-octahedra centered by carbon atoms or C2-groups. The Ln6-octahedra are condensed via opposite edges to chains and surrounded by X atoms which interconnect the chains. A part n of isolated C-atoms is substituted by 1-n C2-groups. The C-C distances range between 1.26 and 1.40 A. In the ionic formulation (Ln3+) 4(X-)5(C4-)n(C 2 m-)1-n · e- with 0 22-, C24- C26-), there are 1 - 5 electrons centered in metal-metal bonds.
Rare-earth iodides in ionic liquids: Crystal structures of [bmpyr]4[LnI6][Tf2N] (Ln = La, Er)
Babai, Arash,Mudring, Anja-Verena
, p. 122 - 127 (2006)
Deliberately designed ionic liquids can be excellent solvents for organic reactions with lanthanide compounds, e.g. Lewis catalysis with trivalent lanthanides. Little is known about the solvation and complexation of these Lewis-acid catalysts in these-still uncommon-solvents, although the knowledge of these processes is a prerequisite for a basic understanding of reaction mechanisms and catalytic cycles. Therefore, we have investigated the chemical behaviour of rare-earth metal iodides in the ionic liquid [bmpyr][Tf2N] (bmpyr = 1,1-n-butyl-methylpyrrolidinium; Tf2N = bis(trifluoromethanesulfonyl)-amide). Compounds of the general composition [bmpyr]4[LnI6][Tf2N] could be crystallized from solutions of LnI3 (Ln = La, Er), in [bmpyr][Tf2N]. Single-crystal X-ray diffraction data show that the trivalent rare-earth cations are octahedrally coordinated by six iodide anions. Eight cations of the ionic liquid are located tangentially above each of the triangular faces of the [LnI6] octahedron. According to the size of the trivalent cation, the crystal structure adjusts itself by tilting of the [LnI6] octahedra to accommodate one anion of the ionic liquid, bis(trifluoromethanesulfonyl)-amide, which completes the crystal structure of the composition [bmpyr]4[LnI6][Tf2N].
La2Tel2: A new layered telluride iodide with unusual electrical properties
Ryazanov, Mikhail,Simon, Arndt,Mattausch, Hansjurgen
, p. 10728 - 10733 (2006)
A new layered metal-rich telluride halide, La2Tel2, has been synthesized by heating stoichiometric mixtures of Lal3, La, and Te under argon at 900°C, and its structure has been refined from X-ray powder diffraction data. The compound crystallizes in the 3R-Lu 2CCl2 structure type (rhombohedral space group R3m with a = 4.5074(4) A, c = 32.528(2) A, and Z = 3). The crystal structure is composed of infinite layers of edge-sharing, Te-centered metal atom octahedra and iodine atoms separating these layers to form three close-packed I-Ln-Te-Ln-I slabs within the unit cell. The title compound is metallic at room temperature and exhibits an anomaly in the resistivity around 140 K which is closely related to changes in the a lattice parameter with temperature. The chemical bonding and metallic properties of La2Tel2 can be plausibly understood in terms of an ionic description (Ln3+)2Te 2-(I-)2(e)2 where two electrons are delocalized in the La 5d conduction band.
LiLa6I12Os, a substitutional derivative of rhombohedral La(La6I12Os)
Jensen, Elizabeth A.,Corbett, John D.
, p. 4465 - 4474 (2004)
The series of quaternary rare-earth-metal halide cluster compounds ALa 6I12Z with transition metal interstitials Z and alkali or alkaline-earth metal cations A has been expanded to include A=Li. The compounds synthesized by high-temperature solid-state techniques for Z=Os, Ir, Pt, Ru are isotypic with rhombohedral R7X12Z (R3, Z=3). The refined single X-ray crystal structure of (Li0.967La 0.033)La6I12Os is reported, along with supportive results from a Rietveld analysis of neutron powder diffraction from a different sample, 7Li MAS-NMR, and electronic resistivity and magnetic susceptibility measurements. The samples show continuous Li 1-xLax cation compositions and are generally semiconductors, but their complex paramagnetic properties are not those of simple spin-only systems.
The structural change of lanthanum diiodide upon hydrogenation
Ryazanov,Simon,Mattausch,Kremer
, p. 142 - 145 (2004)
Slowly heating LaI2 under 1atm hydrogen to 650°C leads to LaI2H, analyzed as LaI2H0.95(3), accompanied by a structural change from tetragonal to hexagonal. Sharp reflections in the XRD pattern can be indexed in P63/mmc with a=4.2158(7)A? and c=15.508(3)A?, however, diffuse reflections indicate a polytypic intergrowth of MoS2 and NbS2 type structures. The earlier determined miscibility gap between LaI2 and LaI2H x (x≈0.5) is closely related to the change of the structure. The Pauli paramagnetism for LaI2, χP = 43(2)×10 -6cm3/mol, derived from measurements on LaI2 and LaI2H is in good agreement with the value estimated from band structure calculations.
The aluminide iodides La24Al12I21 and La10Al5I8: Compounds with intermetallic La-A1 fractions and La-Al clusters
Mattausch, Hansjuergen,Oeckler, Oliver,Hoch, Constantin,Simon, Arndt
, p. 1233 - 1238 (2006)
Reacting pieces of La, LaI3 and A1 filings (molar ratio 22: 8: 15) at 800 °C-825 °C results in La24Al12I 21 (70% yield) together with La10Al5I 8 (10 % yield), besides known La3Al2I 2 and La2Al2I. Both new compounds form golden coloured needles. La10Al5I8 is brittle, whereas La24Al12I21 is shaped as hair-like easily deformable bundles. Both are monoclinic, space group C2/m, La 24Al12I21 with a = 35.753(7) A, b = 4.327(1) A, c = 27.442(6) A, β = 116.62(3)° and La 10Al5I8 with a = 19.649(1) A, b = 4.296(1) A, c = 18.0290(1) A and β = 96.67(3)°. The La atoms form trigonal prisms condensed into double chains along [010]. The La prisms are centered by A1 atoms which form Al6 rings connected into chains. The La-Al strands are surrounded by I atoms in La24Al 12I21, whereas in La10Al5I 8 they are connected to form corrugated sheets separated by close packed layers of I atoms together with Al atoms. The octahedral voids around the Al atoms are occupied by La atoms, and such La6Al clusters are connected via opposite edges to octahedra chains along [010].
Investigations on iodomercurates: Crystal structures of bis[di(12-crown-4)lithium]octaiodotrimercurate(II) and catena-poly{di[(benzo-15-crown-5)potassium]pentaiododimercurate(II)} with new iodomercurate anions and a lanthanum(III) tetraidomercurate(II), [La6(OH)8(O)(H2O)24][HgI 4]4 with a hexanuclear complex cation
Pickardt,Wiese,Von Chrzanowski,Borowski
, p. 2096 - 2102 (2000)
By diffusion of methanolic solutions of LiI/HgI2 and 12-crown-4, resp. crystals of [Li(12-crown-4)2]2[Hg3I8] (1) were obtained. They contain a new finite octaiodotrimercurate(II) ion which, contrary to the twisted [Hg3I8]2- ion known so far, is built up linearity from three [HgI4] tetrahedra sharing common edges. From solutions of KI, HgI2, and benzo-15-crown-5, a complex of formal composition [K(benzo-15-crown-5)2][Hg2I5] (2) was formed containing a polymeric iodomercurate ion with a chain structure built up from [Hg2I6] units trans connected by common iodide ions. On both sides of the chains [K(benzo-15-crown-5)2]+ cations are bounded by CH...I interactions. From an aqueous solution of LaI3/HgI2 the hexanuclear complex [La6(H2O)24-(OH)8(O)][(HgI 4)4] (3) was obtained. The six La(III) ions form an octahedron with an O ion in the center, eight three dentate OH ions situated above the faces of the octahedron bind to the three La ions forming the face. Each La ion is further bound to four coordination water molecules. Cations and anions are connected via H bonds.
Substitution experiments on superconducting La2C2X2 (X = Cl, Br, I)
Ahn,Mattausch,Simon
, p. 619 - 622 (1997)
The layered carbide bromide La2C2Br2 becomes superconducting at 6.2 K. We studied the matrix effect on Tc due to (isoelectronic) halogen substitution. Tc increases with the amount of substitution by chlorine to a maximum value of 7.2 K, and it decreases when Br- is partially substituted by I-. La2C2I2 itself is non-superconducting down to 2 K. However, substitution of I- by 10% Cl- leads to superconductivity at 2.2 K.
Some phosphide halides of lanthanum and related compounds
Oeckler, Oliver,Mattausch, Hansjürgen,Simon, Arndt
, p. 1377 - 1382 (2007)
The pnictide halides La2I2P, La2I 2As, La2I2Sb, La2Br2P and Y2Br2P have been synthesized from lanthanum and yttrium, red phosphorus, arsenic, and
