Reverse charge transfer and decomposition in Ca-Te compounds under high pressure.

Pressure alters the nature of chemical bonds and triggers novel reactions. Here, we employed first-principles calculations combined with the CALYPSO structural search technique to reveal the charge transfer reversal between Ca and Te under high pressure in the calcium-tellurium compound (CaTe, = 1/4, 1/3, 1/2, 2/3). We predict several new phases with conventional and unconventional compounds and found an unfamiliar phenomenon: the Ca-Te compounds will reverse charge transfer between Ca and Te atoms and decompose into elemental solids under pressure.

Pressure induced weakness of electrostatic interaction and solid decomposition in Cs-I compounds.

This work utilized first-principles calculations and the CALYPSO structure search technique to systematically investigate the crystal structure stability of CsI compounds under high pressures ranging from 0 to 500 GPa. Several new phases with both conventional and unconventional stoichiometries were predicted. Interestingly, we discovered a counter-intuitive phenomenon where Cs-I compounds decompose into Cs and I elemental solids under pressure.

Mechanochemistry and the Evolution of Ionic Bonds in Dense Silver Iodide.

External mechanical stress alters the nature of chemical bonds and triggers novel reactions, providing interesting synthetic protocols to supplement traditional solvent- or thermo-based chemical approaches. The mechanisms of mechanochemistry have been well studied in organic materials made of a carbon-centered polymeric framework and covalence force field. They convert stress into anisotropic strain which will engineer the length and strength of targeted chemical bonds.

Platelet membrane receptor P2Y12 H1/H2 polymorphism is highly associated with cerebral infarction: a case-control study.

Objectives: This study aimed to determine the relationship between the polymorphisms of the gene of platelet membrane receptor P2Y12 and cerebral infarction (CI) in a Han population in North Shandong Province, People's Republic of China.

Patients And Methods: A case-control study, which involved 168 nonstoke subjects (contrast group) and 152 CI patients (CI group), was conducted. The state of subjects in the CI group was validated by computed tomography or MRI.