Structure-Based Phase Diagram of LaFeAs_xP_1-xO 1111 System

In this talk, I will be reporting the structural and physical properties of high quality powder samples of LaFeAs_xP_1-xO from x=0 to x=1 examined using high resolution x-ray and neutron diffraction. This system is of interest due to similarities to the 122 system where novel magnetic phases were discovered in co-existence with superconductivity. To investigate such similarities, multiple samples bordering reported antiferromagnetic and superconducting regions were prepared. While preliminary analysis confirms the existence of AFM properties with low P doping, neutron data revealed no evidence for the AFM2 phase that was previously reported in the literature centered around x=0.5. I will be discussing the full details of the current state of the phase diagram.