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Notes: Sintered disks of TiO2 (rutile) have been exposed to the beam of a 355 nm laser. X-ray photoelectron spectroscopy studies show that the strong energy deposition at the surface is responsible for the formation of Ti3+ ions down to a depth of 0.4 μm. The presence of these ions produces a large decrease in the electrical resistivity from 109 Ω cm in nonirradiated TiO2 to 10 Ω cm after laser treatment. Temperature dependent resistance measurements indicate that the creation of Ti3+ ions leads to the formation of energy levels in the gap and to a hopping-driven conduction at room temperature.

Notes: Ternary fluorides LnMoF7 have been synthesized by solid-state reactions between MoF4 and LnF3 for yttrium and all lanthanides except dysprosium. These compounds are all monoclinic, space group P21; they are isotypic with the LnZrF7 and LnNbF7 compounds. Unit-cell parameters for the 14 compounds are: LaMoF7: a = 6.3952(4), b = 5.6285(4), c = 8.4351(5) Å, β = 102.695(6)°, V = 296.2(5) Å3, Z = 2, Dx = 4.12 Mg m−3; CeMoF7: a = 6.3275(5), b = 5.6657(5), c = 8.4122(7) Å, β = 102.985(7)°, V = 293.9(5) Å3, Z = 2, Dx = 4.17 Mg m−3; PrMoF7: a = 6.3155(5), b = 5.6599(7), c = 8.4167(6) Å, β = 102.946(6)°, V = 293.2(5) Å3, Z = 2, Dx = 4.19 Mg m−3; NdMoF7: a = 6.1152(4), b = 5.6983(4), c = 8.2914(5) Å, β = 103.201(6)°, V = 281.3(5) Å3, Z = 2, Dx = 4.41 Mg m−3; SmMoF7: a = 6.0686(4), b = 5.6503(6), c = 8.2261(5) Å, β = 103.246(5)°, V = 274.6(4) Å3, Z = 2, Dx = 4.59 Mg m−3; EuMoF7: a = 6.0337(5), b = 5.6311(4), c = 8.1953(5) Å, β = 103.420(6)°, V = 270.8(4) Å3, Z = 2, Dm = 4.63, Dx = 4.67 Mg m−3; GdMoF7: a = 6.0138(4), b = 5.6241(5), c = 8.1726(5) Å, β = 103.371 (7)°, V = 268.9(5) Å3, Z = 2, Dx = 4.77 Mg m−3; TbMoF7: a = 6.0081(5), b = 5.6621(5), c = 8.1868(5) Å, β = 103.685(7)°, V = 270.6(5) Å3, Z = 2, Dx = 4.76 Mg m−3; HoMoF7: a = 5.9801(4), b = 5.6456(5), c = 8.1282(5) Å, β = 103.465(6)°, V = 266.9(4) Å3, Z = 2, Dx = 4.90 Mg m−3; ErMoF7: a = 5.9293(5), b = 5.5732(5), c = 8.0831(5) Å, β = 103.540(7)°, V = 259.7(5) Å3, Z = 2, Dm = 5.01, Dx = 5.07 Mg m−3; TmMoF7: a = 5.9309(4), b = 5.5976(5), c = 8.1096(4) Å, β = 104.056(5)°, V = 261.2(4) Å3, Z = 2, Dx = 5.06 Mg m−3; YbMoF7: a = 5.8950(4), b = 5.5448(4), c = 8.0199(5) Å, β = 103.552(6)°, V = 254.9(4) Å3, Z = 2, Dx = 5.24 Mg m−3; LuMoF7: a = 5.8593(5), b = 5.5172(5), c = 8.0423(6) Å, β = 103.752(8)°, V = 252.5(6) Å3, Z = 2, Dx = 5.31 Mg m−3; YMoF7: a = 5.9397(4), b = 5.5945(5), c = 8.1108(5) Å, β = 103.643(6), V = 262.0(4) Å3, Z = 2, Dx = 4.03 Mg m−3. The variation of unit-cell data is in agreement with the lanthanidic contraction and the tetrad effect. Powder diffraction data have been obtained at 293 K with a Philips PW1050/25 counter diffractometer; Ni-filtered Cu Kα radiation ({\bar \lambda = 1.5418 Å). The JCPDS Diffraction File Nos. are: LaMoF7 38–1498; CeMoF7 38–1497; PrMoF7 38–1496; NdMoF7 38–1495; SmMoF7 38–1494; EuMoF7 38–1493; GdMoF7 38–1492; TbMoF7 38–1491; HoMoF7 38–1490; ErMoF7 38–1489; TmMoF7 38–1488; YbMoF7 38–1487; LuMoF7 38–1486; YMoF7 38–1485.

Notes: Nd(MoO4) (ReO4) is monoclinic, space group P21/c; the cell dimensions are a = 6.169 (1), b = 9.822 (1), c = 13.139 (2) Å and β = 111.65 (1)°. The monoclinic compounds in the series Ln(MoO4) (ReO4), with Ln = Ce to Lu (Pm compound is not examined), are isotypic. Crystal parameters and powder diffraction data are given.

Notes: Two orthophosphates M1CuPO4 (with M1 = Na or Ag) have been synthesized by solid-state reaction between M3PO4 and Cu3(PO4)2. Each of these compounds undergoes a phase transition at high temperature, for AgCuPO4 the polymorphic transformation is irreversible. α-NaCuPO4 (low temperature) is orthorhombic P212121, a = 9.7098(8), b = 4.8040(3), c = 7.1676(6) Å, V = 334.34(7) Å3, Dm (298 K) = 3.55, Dx = 3.606 Mg m−3, Z = 4. β-AgCuPO4 (high temperature) is orthorhombic, Pbca, a = 7.5008(6), b = 15.749(1), c = 5.7030(5) Å, V = 673.70(14) Å3, Dm(298 K) = 5.25, Dx = 5.253 Mg m−3 for Z = 8. Powder diffraction data have been obtained at 293 K with a counter diffractometer with Ni-filtered copper radiation (λ = 1.5418 Å). The JCPDS Diffraction File Nos. are 34-1496 for β-AgCuPO4; 34-1497 for α-NaCuPO4.