Single-crystal growth and physical properties of the layered arsenide BaRh2As2

TitleSingle-crystal growth and physical properties of the layered arsenide BaRh2As2
Publication TypeJournal Article
Year of Publication2008
AuthorsSingh Y, Lee Y, Nandi S, Kreyssig A, Ellern A, Das S, Nath R, Harmon BN, Goldman AI, Johnston DC
Journal TitlePhysical Review B
Date PublishedSep
Type of ArticleArticle
ISBN Number1098-0121
Accession NumberISI:000259690400088

Single crystals of BaRh2As2 have been synthesized from a Pb flux. We present the room-temperature crystal structure, single-crystal x-ray diffraction measurements as a function of temperature T, anisotropic magnetic susceptibility chi versus T, electrical resistivity in the ab plane rho versus T, Hall coefficient versus T and magnetic field H, and heat capacity C versus T measurements on the crystals. The single-crystal structure determination confirms that BaRh2As2 forms in the tetragonal ThCr2Si2-type structure (space group I4/mmm) with lattice parameters a=b=4.0564(6) angstrom and c=12.797(4) angstrom. Band-structure calculations show that BaRh2As2 should be metallic with a small density of states at the Fermi energy N(E-F)=3.49 states/eV f.u. (where f.u. equivalent to formula unit) for both spin directions. rho(T) data in the ab plane confirm that the material is indeed metallic with a residual resistivity rho(2 K)=29 mu Omega cm and with a residual resistivity ratio rho(310 K)/rho(2 K)=5.3. The observed chi(T) is small (similar to 10(-5) cm(3)/mol) and weakly anisotropic with chi(ab)/chi(c)approximate to 2. The C(T) data indicate a small density of states at the Fermi energy with the low-temperature Sommerfeld coefficient gamma=4.7(9) mJ/mol K-2. There are no indications of superconductivity, spin-density wave, or structural transitions between 2 and 300 K. We compare the calculated density of states versus energy of BaRh2As2 with that of BaFe2As2.

Alternate JournalPhys. Rev. B