Compression of Zr2InC to 52 GPa

Using a synchrotron-radiation source and a diamond-anvil cell, we measured the pressure dependence of the lattice parameters of a polycrystalline Zr2InC sample. Up to a pressure of 52 GPa, no phase transformations were observed. As observed in Ti3SiC2 and Ti3Si0.5Ge0.5C2, the compressibility of Zr2InC along the c axis was greater than along the a axis. The bulk modulus is 127+/-5 GPa, with a pressure derivative of 4.25+/-0.3; the former is in excellent agreement with our ab initio calculations (130.9 GPa). The a (3.367 A) and c (15.100 A) parameters from the ab initio calculations are also slightly larger than those measured here, viz., 3.35 and 14.91 A. Surprisingly, a hysteresis was observed in the a-lattice parameters; they were higher upon unloading than loading. The reason for this hysteresis is not clear at this time. (C) 2004 American Institute of Physics.