Electronic Structure Calculations for Cr 1-x Al x

1. Electronic Structure Calculations for Cr1-xAlx Daniel C. Ralph, Cornell University, ECCS - 0335765 Intermetallic compounds containing transition metals and sp elements often form a gap at the Fermi energy due to hybridization. This gap can be exploited for applications such as thermoelectric devices. Cr3Al is anomalous in that experiments demonstrate that it is an insulating antiferromagnet with a gap at the Fermi energy, while standard theories predict that it should be a metal. We investigated this odd behavior using the computational resources of the CNF by performing electronic structure calculations for Cr and Cr1-xAlx alloys. We observed shifts in the band structure upon alloying that explain the evolution of Hall effect measurements and a significant reduction in the Fermi surface in Cr0.80Al0.20, but not a full gap. Ongoing work is examining whether the gap is the result of an ordered structure. Cr Cr0.80Al0.20 Z. Boekelheide, F. Hellman, University of California, Berkeley Work performed at Cornell NanoScale Facility Calculated Bloch spectral function of pure Cr and disordered Cr0.80Al0.20 alloy.