2004 Roster

2004 Women\u27s Softball Roster, George Fox College

Remarkable Metal-Rich Ternary Chalcogenides Sc₁₄M₃Te₈ (M = Ru, Os)

In this novel motif, scandium atoms define infinite parallel chains of alternate trans-face-sharing cubes and pairs of square antiprisms in which each polyhedron is also centered by an M atom (M = Ru, Os). These chains are further linked into a three-dimensional structure by Sc(Te2Te4/2) octahedra. Physical property measurements show Sc14Ru3Te8 to be metallic and Pauli-paramagnetic, consistent with the results of extended Hückel band structure calculations. Matrix effects are evident in the dimensions within the chains. The major interactions are Sc−M and Sc−Te

R₆TT‘₂, New Variants of the Fe₂P Structure Type. Sc₆TTe₂ (T = Ru, Os, Rh, Ir), Lu₆MoSb₂, and the Anti-typic Sc₆Te_0.80Bi_1.68

The Fe2P structure (P6̄2m) features two 3-fold Fe positions and both 2-fold and 1-fold P sites, and variations in occupancies of the latter pair yield the reported diversity of results. The known Sc6TTe2 examples for T = Fe−Ni are herein extended to four heavier transition metal T derivatives. An attempt to synthesize bismuth analogues led to the novel inverse derivative in which fractional Te (vice T) occupies the smaller tricapped trigonal prismatic (TTP) Sc polyhedron, and Bi rather than Te occurs in the larger TTP of Sc, with parallel reversal of polarity in the bonding. The reported Lu8Te, which is distributed as Lu6TeLu2, is the only example in which a transition metal occupies the normal 2-fold P or Te non-metal position, with corresponding large effects on the bonding. Lutetium otherwise does not form R6TTe2 analogues, but the novel Lu6MoSb2 isotype occurs instead. Extended Hückel calculations are presented for five examples, and the structural and bonding regularities and varieties are discussed further

Remarkable Metal-Rich Ternary Chalcogenides Sc₁₄M₃Te₈ (M = Ru, Os)

In this novel motif, scandium atoms define infinite parallel chains of alternate trans-face-sharing cubes and pairs of square antiprisms in which each polyhedron is also centered by an M atom (M = Ru, Os). These chains are further linked into a three-dimensional structure by Sc(Te2Te4/2) octahedra. Physical property measurements show Sc14Ru3Te8 to be metallic and Pauli-paramagnetic, consistent with the results of extended Hückel band structure calculations. Matrix effects are evident in the dimensions within the chains. The major interactions are Sc−M and Sc−Te

Lu₈Te and Lu₇Te. Novel Substitutional Derivatives of Lutetium Metal

Monocrystals of Lu8Te are synthesized by disproportionation of Lu7Te at 1000−1200 °C or by direct reaction of Lu plus Lu2Te3 at 1000 °C for 2 weeks. Lu7Te is produced by arc-melting of a suitable Lu−Lu2Te3 mixture, with good crystals being formed by subsequent annealing at 1300 °C. The structures of Lu8Te (P6̄2m, Z = 1) and Lu7Te (Cmcm, Z = 4) exhibit simple AB··· packing of distorted, not close-packed, layers along one short axis (c⃗, a⃗, respectively). Puckered Lu, Te layers are stacked normal to (010) or (001) in six- or eight-layer repeat sequences, with Te substituting for every third or every other Lu in every third or fourth layer, respectively. Strong Lu−Te bonding is indicated. Both Te substitutions decrease the volume per atom from that in hcp. Lu and also decrease the coordination number of all atoms from 12 to 9−11

Synthesis, Structure, and Bonding of Sc₆MTe₂ (M = Ag, Cu, Cd): Heterometal-Induced Polymerization of Metal Chains in Sc₂Te

Three new compounds, Sc6AgTe2, Sc6Cu0.80(2)Te2.20(2), and Sc6CdTe2, were prepared by high-temperature solid state techniques, and the structures were determined by single-crystal X-ray diffraction to be orthorhombic, Pnma (No. 62, Z = 4) with a = 20.094(9) Å, 19.853(5) Å, 20.08(1) Å, b = 3.913(1) Å, 3.914(1) Å, 3.915(2) Å, and c = 10.688(2) Å, 10.644(2) Å, 10.679(5) Å, respectively, at 23 °C. The compounds are isotypic with Sc6PdTe2 and represent the first ternary metal-rich rare-earth-metal chalcogenides containing group 11 or group 12 elements. The structure can be viewed as heterometal sheets lying parallel to the b−c planes that are separated by isolated tellurium atoms. These sheets can also be viewed as a polymerization of two different types of metal chains in Sc2Te (blades and zigzag chains) by heterometal (M) replacements of some intervening tellurium atoms. Extended Hückel band calculations reveal that the interior atoms in the metal network achieve negative formal Mulliken charges while Sc atoms on the exterior that have tellurium neighbors have positive values. The heterometal−metal bonding enhances the overlap populations of zigzag chains and blades relative to those in Sc2Te. The calculation results also indicate that these compounds are metallic, as usual

Remarkable Metal-Rich Ternary Chalcogenides Sc₁₄M₃Te₈ (M = Ru, Os)

In this novel motif, scandium atoms define infinite parallel chains of alternate trans-face-sharing cubes and pairs of square antiprisms in which each polyhedron is also centered by an M atom (M = Ru, Os). These chains are further linked into a three-dimensional structure by Sc(Te2Te4/2) octahedra. Physical property measurements show Sc14Ru3Te8 to be metallic and Pauli-paramagnetic, consistent with the results of extended Hückel band structure calculations. Matrix effects are evident in the dimensions within the chains. The major interactions are Sc−M and Sc−Te

Synthesis, Structure, and Bonding of Lu₇Z₂Te₂ (Z = Ni, Pd, Ru). Linking Typical Tricapped Trigonal Prisms in Metal-Rich Compounds

The syntheses and structures of and bonding in the title compounds are described and compared with those for the isostructural orthorhombic Er7Ni2Te2 (Imm2) and other related phases. Single-crystal data are reported for Z = Ni, Pd. The condensation of tricapped trigonal prisms (TTP) into sheets and the bridging of these by separate Lu atoms into a 3D structure are described. The interlayer separation, the Lu−Lu bonding achieved, and the polar Lu−Te bonding therewith are all affected by the size and valence energies of Te. The two Te spacers also exist in capped centered Lu6Te trigonal prisms. In terms of extended Hückel band analyses, the overall bonding for both Lu−Ni and Lu−Te are optimized energetically, but not for Lu−Lu. The average Lu−Lu overlap populations about each Lu appropriately increase with a decrease in the number of its Te neighbors

Colorimetric Detection of Mercury Species Based on Functionalized Gold Nanoparticles

The speciation analysis of heavy metal pollutants is very important because different species induce different toxicological effects. Nanomaterial-assisted optical sensors have achieved rapid developments, displaying wide applications to heavy metal ions but few to metal speciation analysis. In this work, a novel colorimetric nanosensor strategy for mercury speciation was proposed for the first time, based on the analyte-induced aggregation of gold nanoparticles (Au NPs) with the assistance of a thiol-containing ligand of diethyldithiocarbamate (DDTC). Upon the addition of mercury species, because Hg-DDTC was more stable than Cu-DDTC, a place-displacement between Hg species and Cu2+ would occur, and thereby the functionalized Au NPs would aggregate, resulting in a color change. Moreover, by virtue of the masking effect of ethylenediaminetetraacetic acid (EDTA), the nanosensor could readily discriminate organic mercury and inorganic mercury (Hg2+), and it is thus anticipated to shed some light on the colorimetric sensing of organic mercury. So, a direct, simple colorimetric assay for selective determination of Hg species was obtained, presenting high detectability, such as up to 10 nM for Hg2+ and 15 nM for methylmercury. Meanwhile, the strategy offered excellent selectivity toward mercury species against other metal ions. The simple, rapid, and sensitive label-free colorimetric sensor for the determination of Hg species provided an attractive alternative to conventional methods, which usually involve sophisticated instruments, complicated processes, and long periods of time. More importantly, by using mercury as a model, an excellent nanomaterial-based optical sensing platform can be developed for speciation analysis of trace heavy metals, which can lead to nanomaterials stability change through smart functionalization and reasonable interactions

Lu₈Te and Lu₇Te. Novel Substitutional Derivatives of Lutetium Metal

Monocrystals of Lu8Te are synthesized by disproportionation of Lu7Te at 1000−1200 °C or by direct reaction of Lu plus Lu2Te3 at 1000 °C for 2 weeks. Lu7Te is produced by arc-melting of a suitable Lu−Lu2Te3 mixture, with good crystals being formed by subsequent annealing at 1300 °C. The structures of Lu8Te (P6̄2m, Z = 1) and Lu7Te (Cmcm, Z = 4) exhibit simple AB··· packing of distorted, not close-packed, layers along one short axis (c⃗, a⃗, respectively). Puckered Lu, Te layers are stacked normal to (010) or (001) in six- or eight-layer repeat sequences, with Te substituting for every third or every other Lu in every third or fourth layer, respectively. Strong Lu−Te bonding is indicated. Both Te substitutions decrease the volume per atom from that in hcp. Lu and also decrease the coordination number of all atoms from 12 to 9−11