Structure and properties of a novel boride: ThNi12B6

Author(s)

Soner Steiner, Gerda Rogl, Herwig Michor, Peter Franz Rogl, Gerald Giester, António Pereira Gonçalves

Abstract

Investigation of the system Th-Ni-B prompted a novel ternary compound ThNi

₁₂B

₆. X-ray structure analysis of single crystals obtained by the mechanical fragmentation of an as-cast sample revealed a fully ordered CeNi

₁₂B

₆-type structure (space group Cmc2

₁, no. 36; a = 0.95638(1) nm, b = 0.73852(1) nm, c = 1.10195(1) nm; R

_F2 = 0.0305). Density functional theory (DFT) calculations have been performed comprising heat of formation, electronic band structure and density of states, Fermi surface via Wannier functions, phonon band structure and density of states, phonon and electronic contributions to specific heat and elastic constants C

_ij. Comparing the parameters evaluated from DFT with the experimental data, an overall satisfactory agreement has been achieved. Measurements of electrical resistivity, magnetic susceptibility and specific heat manifest a Pauli paramagnetic, metallic behaviour for ThNi

₁₂B

₆ without any anomalies, in close match with the isotypic homologue LaNi

₁₂B

₆. Static and dynamic hardness data show rather high values; Young's modulus is in the range of 240 GPa. The Debye temperature,

_D = 490 K, gained via elastic constants, is slightly higher than the values extracted from specific heat or electrical resistivity data. A rather low coefficient of thermal expansion, α = 5.5 × 10

^-6 K

^-1, was derived from the temperature dependent length change.

Organisation(s)

Department of Materials Chemistry, Department of Mineralogy and Crystallography

External organisation(s)

Technische Universität Wien, Universidade de Lisboa

Journal

Dalton Transactions

Volume

47

Pages

12933-12943

No. of pages

11

ISSN

1477-9226

DOI

https://doi.org/10.1039/c8dt02601g

Publication date

09-2018

Peer reviewed

Yes

Austrian Fields of Science 2012

104003 Inorganic chemistry, 104017 Physical chemistry, 104011 Materials chemistry, 105113 Crystallography

Keywords

ASJC Scopus subject areas

Inorganic Chemistry

Portal url

https://ucrisportal.univie.ac.at/en/publications/4e73641a-7a89-467c-a95f-aba360e0bdea