Crystal structure and superconductivity of TiZr up to 57 GPa

The crystal structure of the equiatomic TiZr alloy is studied in the pressure range up to 57 GPa using the diamond anvils and synchrotron radiation. It is found that this alloy follows the alpha-->omega-->beta transition series earlier observed on Zr and Hf. Superconductivity measurements on the same alloy to 47 GPa show that the transition to the bcc beta phase is connected with an increase in the superconducting transition temperature to 15 K. The pressure dependence of the atomic volume is fitted to an equation of state. Low values of the pressure derivative of the bulk modulus as well as the increase in the superconducting transition temperature are discussed in terms of a pressure-induced s-d electron transfer.