Anharmonic thermal vibration and crystal structure refinements

Solid–Solid Synthesis, Crystal Structure and Thermal Decomposition of Copper(II) Complex of 2-Picolinic Acid

The copper(II) complex [Cu(pic)2]·2H2O was synthesized with 2-picolinic acid (Hpic) and copper acetate as reactants by room temperature solid-solid reaction. The composition and structure of the complex was characterized by elemental analyses, single crystal X-ray diffraction, X-ray powder diffraction, FT-IR spectroscopy and thermogravimetry-differential scanning calor...

Crystal structure of post-perovskite-type CaIrO3 reinvestigated: new insights into atomic thermal vibration behaviors

Single crystals of the title compound, the post-perovskite-type CaIrO3 [calcium iridium(IV) trioxide], have been grown from a CaCl2 flux at atmospheric pressure. The crystal structure consists of an alternate stacking of IrO6 octa-hedral layers and CaO8 hendeca-hedral layers along [010]. Chains formed by edge-sharing of IrO6 octa-hedra (point-group symmetry 2/m..) run along [100] and are inter-...

Single-crystal structure refinements and crystal chemistry of synthetic trioctahedral micas

To study structural changes with changing chemical composition in the octahedral sheet of trioctahedral potassium-rich 1M micas, 3 natural and 12 synthetic micas were examined by singlecrystal X-ray diffraction. Samples with Ni, Mg, Co, Fe, and Al in the octahedral sheet and with Si, Al and one sample with Ga in the tetrahedral sheet were prepared at high temperatures and pressures, which yield...

Thermal vibration amplitudes and structure of As on Si(001).

Structure, dynamics and phase transitions Anharmonic phonons and negative thermal expansion in ScF3 and Ag2O

We report progress towards understanding how phonon anharmonicity contributes to negative thermal expansion (NTE). Some contribution to the NTE is from "quasiharmonic" behavior, where phonon frequencies decrease as a crystal expands. A second "anharmonic" effect from phonon-phonon interactions is sometimes calculated by perturbation theory, but sometimes the anharmonic effects are too large to ...