No abstract

We measured in-plane X-ray diffraction and investigated the strained lateral structure and its relaxation in a Cu2O thin crystal epitaxially grown in a small gap between paired MgO substrates. Although one side MgO was peeled off to irradiate Cu2O with X-ray, a thin MgO layer remained on Cu2O, and diffraction peaks of (400)-planes in both MgO and Cu2O were detected. The peak has four-fold symmetry on sample rotation, and the lattice constant estimated from the diffraction angle is 4.254 Å. The lattice constant is larger than that of MgO and smaller than that of strain-free Cu2O. Furthermore, it was found that the lattice strain in Cu2O relaxes at a depth of ≈0.15 μm from MgO on the basis of the estimated X-ray penetration depth under consideration of low incident angle, absorption and refraction of X-ray.

No abstract

No abstract

The structural and electronic properties of liquid CdTe under pressure are studied by ab initio molecular dynamics simulations. It is shown that the pressure dependence of the static structure factor observed by the recent x-ray-diffraction experiments is successfully reproduced by our simulations for a wide range of pressure up to about 20 GPa. The population analysis, as well as the electronic density of states, reveals that the covalent-bonding interaction between Cd and Te atoms is retained in the liquid state below 4 GPa. It is found that short-range correlations between like atoms become important at higher pressures accompanying metallization, i.e., Cd-Cd and Te-Te correlations appear in the first-coordination shell around each Cd and Te above about 4 and 8 GPa, respectively.