Publications (6) View all
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Article: Surface and Bulk Structural Properties of Single Crystalline Sr3Ru2O7
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ABSTRACT: We report temperature and thermal-cycling dependence of surface and bulk structures of double-layered perovskite Sr3Ru2O7 single crystals. The surface and bulk structures were investigated using low-energy electron diffraction (LEED) and single-crystal X-ray diffraction (XRD) techniques, respectively. Single-crystal XRD data is in good agreement with previous reports for the bulk structure with RuO6 octahedral rotation, which increases with decreasing temperature (~ 6.7(6)degrees at 300 K and ~ 8.1(2) degrees at 90 K). LEED results reveal that the octahedra at the surface are much more distorted with a higher rotation angle (~ 12 degrees between 300 and 80 K) and a slight tilt ((4.5\pm2.5) degrees at 300 K and (2.5\pm1.7) degrees at 80 K). While XRD data confirms temperature dependence of the unit cell height/width ratio (i.e. lattice parameter c divided by the average of parameters a and b) found in a prior neutron powder diffraction investigation, both bulk and surface structures display little change with thermal cycles between 300 and 80 K. Comment: 25 pages, 5 figures, 5 tables, to appear in Physical Review B03/2010; -
Article: Structure and magnetism of the quasi-1-d K4Cu(MoO4)3 and the structure of K4Zn(MoO4)3.
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ABSTRACT: Single crystals of K(4)Cu(MoO(4))(3) and nonmagnetic K(4)Zn(MoO(4))(3) have been grown by the flux-growth method. K(4)Cu(MoO(4))(3) can be described as a quantum quasi-1-d antiferromagnet with correlations between neighboring Cu(2+) ions but no magnetic long-range ordering down to 0.4 K. Comparison of the structure and magnetic properties of isostructural A(4)Cu(MoO(4))(3) (A = K, Rb) allows the isolation of the effects of low dimensionality from structural distortion along the Cu-O-Mo chains. The characteristic one-dimensional behavior is hence suppressed to lower the temperature in K(4)Cu(MoO(4))(3) in comparison with that of the Rb analogue. For example, a broad peak in the specific heat is observed ~2.3 K at 0 T, which is consistent with the onset of the quantum spin liquid state.Inorganic Chemistry 08/2011; 50(18):8767-73. · 4.60 Impact Factor -
Article: (5SR,10SR,15SR)-Trimethyl 5H,10H,15H-diindeno[1,2-a:1′,2′-c]fluorene-5,10,15-tricarboxylate 0.167-hydrate
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ABSTRACT: The title compound, C33H24O6·0.17H2O, which is commonly known as (SR,SR,SR)-trimethyl 1,10,19-truxentricarboxylate, crystallizes as a hydrate with the water molecule encapsulated between three ester groups by O—H...O hydrogen bonding to two of them. The water molecule site is not fully occupied in the crystal studied, with a refined site occupancy of 0.167 (5). The 27-atom ring system is approximately planar, with a maximum deviation of 0.148 (1) Å, and the three ester substituents are all on the same side of this plane.Acta Crystallographica Section E. 01/2011; -
Article: (5SR,10SR,15SR)-Trimethyl 5H,10H,15H-diindeno-[1,2-a:1',2'-c]fluorene-5,10,15-tricarboxyl-ate 0.167-hydrate.
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ABSTRACT: The title compound, C(33)H(24)O(6)·0.17H(2)O, which is commonly known as (SR,SR,SR)-trimethyl 1,10,19-truxentricarboxyl-ate, crystallizes as a hydrate with the water mol-ecule encapsulated between three ester groups by O-H⋯O hydrogen bonding to two of them. The water mol-ecule site is not fully occupied in the crystal studied, with a refined site occupancy of 0.167 (5). The 27-atom ring system is approximately planar, with a maximum deviation of 0.148 (1) Å, and the three ester substituents are all on the same side of this plane.Acta Crystallographica Section E Structure Reports Online 01/2010; 67(Pt 1):o1-2. · 0.35 Impact Factor -
Article: Surface and bulk structural properties of single-crystalline Sr_ {3} Ru_ {2} O_ {7}
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ABSTRACT: We report temperature and thermal-cycling dependence of surface and bulk structures of double-layered perovskite Sr3Ru2O7 single crystals. The surface and bulk structures were investigated using low-energy electron diffraction (LEED) and single-crystal x-ray diffraction (XRD) techniques, respectively. Single-crystal XRD data is in good agreement with previous reports for the bulk structure with RuO6 octahedral rotation, which increases with decreasing temperature [∼6.7(6)° at 300 K and ∼8.1(2)° at 90 K]. LEED results reveal that the octahedra at the surface are much more distorted with a higher rotation angle (∼12° between 300 and 80 K) and a slight tilt [(4.5±2.5)° at 300 K and (2.5±1.7)° at 80 K]. While XRD data confirms temperature dependence of the unit-cell height/width ratio (i.e., lattice parameter c divided by the average of parameters a and b) found in a prior neutron-powder-diffraction investigation, both bulk and surface structures display little change with thermal cycles between 300 and 80 K.Phys. Rev. B. 81(18).
