${\mathrm{Ca}}_{10}$(${\mathrm{Pt}}_3{\mathrm{As}}_8$)(${\mathrm{Fe}}_2{\mathrm{As}}_2$)${}_5$ is the parent compound for a class of Fe-based high-temperature superconductors where superconductivity with transition temperatures up to 30 K can be introduced by partial element substitution. We present a combined high-resolution high-energy x-ray diffraction and elastic neutron scattering study on a ${\mathrm{Ca}}_{10}$(${\mathrm{Pt}}_3{\mathrm{As}}_8$)(${\mathrm{Fe}}_2{\mathrm{As}}_2$)${}_5$ single crystal. This study reveals the microscopic nature of two distinct and continuous phase transitions to be very similar to other Fe-based high-temperature superconductors: an orthorhombic distortion of the high-temperature tetragonal Fe-As lattice below $T_{\mathrm{S}}=110\left(2\right)$ K followed by stripelike antiferromagnetic ordering of the Fe moments below $T_{\mathrm{N}}=96\left(2\right)$ K. These findings demonstrate that major features of the Fe-based high-temperature superconductors are very robust against variations in chemical constitution as well as structural imperfection of the layers separating the Fe-As layers from each other and confirms that the Fe-As layers primarily determine the physics in this class of material.

• Received 29 June 2014
• Revised 26 August 2014

DOI:https://doi.org/10.1103/PhysRevB.90.100504