New examples of ternary rare-earth metal boride carbides containing finite boron carbon chains: The crystal and electronic structure of RE15B6C20 (RE=Pr, Nd)

Details New examples of ternary rare-earth metal boride carbides containing finite boron carbon chains: The crystal and electronic structure of RE15B6C20 (RE=Pr, Nd) New examples of ternary rare-earth metal boride carbides containing finite boron carbon chains: The crystal and electronic structure of RE15B6C20 (RE=Pr, Nd)

Aug 2008

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2008jssch.181.1882b&link_type=abstract

Journal of Solid State Chemistry, Volume 181, Issue 8, p. 1882-1890.

Other

1

Scientific paper

The ternary rare-earth metal boride carbides RE15B6C20 (RE=Pr, Nd) were synthesized by co-melting the elements. They exist above 1270 K. Their crystal structures were determined from single-crystal X-ray diffraction data. Both crystallize in the space group P1¯, Z=1, a=8.3431(8) Å, b=9.2492(9) Å, c=8.3581(8) Å, α=84.72(1)°, β=89.68(1)°, γ =84.23(1)° (R1=0.041 (wR2=0.10) for 3291 reflections with Io>2σ(Io)) for Pr15B6C20, and a=8.284(1) Å, b=9.228(1) Å, c=8.309(1) Å, α=84.74(1)°, β=89.68(1)°, γ=84.17(2)° (R1=0.033 (wR2=0.049) for 2970 reflections with Io>2σ(Io)) for Nd15B6C20. Their structure consists of a three-dimensional framework of rare-earth metal atoms resulting from the stacking of slightly corrugated and distorted square nets, leading to cavities filled with unprecedented B2C4 finite chains, disordered C3 entities and isolated carbon atoms, respectively. Structural and theoretical analyses suggest the ionic formulation (RE3+)15([B2C4]6-)3([C3]4-)2(C4-)2·11ē. Accordingly, density functional theory calculations indicate that the compounds are metallic. Both structural arguments as well as energy calculations on different boron vs. carbon distributions in the B2C4 chains support the presence of a CBCCBC unit. Pr15B6C18 exhibits antiferromagnetic order at TN=7.9 K, followed by a meta-magnetic transition above a critical external field B>0.03 T. On the other hand, Nd15B6C18 is a ferromagnet below TC≈40 K.

Affiliated with

Also associated with

No associations

Rating

New examples of ternary rare-earth metal boride carbides containing finite boron carbon chains: The crystal and electronic structure of RE15B6C20 (RE=Pr, Nd) does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with New examples of ternary rare-earth metal boride carbides containing finite boron carbon chains: The crystal and electronic structure of RE15B6C20 (RE=Pr, Nd), we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and New examples of ternary rare-earth metal boride carbides containing finite boron carbon chains: The crystal and electronic structure of RE15B6C20 (RE=Pr, Nd) will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1795358