New kagome prototype materials: discovery of KV 3 Sb 5 , RbV 3 Sb 5 , and CsV 3 Sb 5

In this work, we present our discovery and characterization of a new kagome prototype structure, ${\mathrm{KV}}_{3}{\mathrm{Sb}}_{5}$. We also present the discovery of the isostructural compounds ${\mathrm{RbV}}_{3}{\mathrm{Sb}}_{5}$ and ${\mathrm{CsV}}_{3}{\mathrm{Sb}}_{5}$. All materials exhibit a structurally perfect two-dimensional kagome net of vanadium. Density-functional theory calculations indicate that the materials are metallic, with the Fermi level in close proximity to several Dirac points. Powder and single-crystal syntheses are presented, with postsynthetic treatments shown to deintercalate potassium from single crystals of ${\mathrm{KV}}_{3}{\mathrm{Sb}}_{5}$. Considering the proximity to Dirac…

• NS
  National Science Foundation

  Awards: DMR-1508249, 1729149, 1729594, 1650114, 1437106
• DA
  David and Lucile Packard Foundation
• UD
  U.S. Department of Energy

  Awards: DE-SC0019331, DE-AC02-06CH11357
• FN
  Fundacja na rzecz Nauki Polskiej
• OO
  Office of Science

  Award: DE-SC0017752
• UO
  University of California, Santa Barbara

  Award: 1720256
• MR
  Materials Research Science and Engineering Center, Harvard University
• BE
  Basic Energy Sciences