Structural stability of binary CdCa quasicrystal under high pressure

The structural stability of a binary CdCa quasicrystal with a primitive ico sahedral structure has been investigated by in situ high-pressure x-ray pow der diffraction at an ambient temperature using synchrotron radiation. It i s demonstrated that the icosahedral quasicrystalline structure of the sampl e is intrinsically stable up to 47 GPa. The bulk modulus at zero pressure a nd its pressure derivative of the icosahedral CdCa quasicrystal is 68.1 +/- 2.0 GPa and 4.3 +/-0.2, respectively. The compression behavior of different Bragg peaks is isotropic, indicating no pressure-induced anisotropic elast icity in the stable binary icosahedral CdCa quasicrystals. (C) 2001 America n Institute of Physics.