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Title: Comment on “New Ground-State Crystal Structure of Elemental Boron”

Authors:
; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1351705
Grant/Contract Number:
AC52-07NA27344; SC0014506
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 118; Journal Issue: 15; Related Information: CHORUS Timestamp: 2017-04-12 22:12:03; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society
Country of Publication:
United States
Language:
English

Citation Formats

Ogitsu, Tadashi, Lordi, Vincenzo, Schwegler, Eric, and Widom, Michael. Comment on “New Ground-State Crystal Structure of Elemental Boron”. United States: N. p., 2017. Web. doi:10.1103/PhysRevLett.118.159601.
Ogitsu, Tadashi, Lordi, Vincenzo, Schwegler, Eric, & Widom, Michael. Comment on “New Ground-State Crystal Structure of Elemental Boron”. United States. doi:10.1103/PhysRevLett.118.159601.
Ogitsu, Tadashi, Lordi, Vincenzo, Schwegler, Eric, and Widom, Michael. Wed . "Comment on “New Ground-State Crystal Structure of Elemental Boron”". United States. doi:10.1103/PhysRevLett.118.159601.
@article{osti_1351705,
title = {Comment on “New Ground-State Crystal Structure of Elemental Boron”},
author = {Ogitsu, Tadashi and Lordi, Vincenzo and Schwegler, Eric and Widom, Michael},
abstractNote = {},
doi = {10.1103/PhysRevLett.118.159601},
journal = {Physical Review Letters},
number = 15,
volume = 118,
place = {United States},
year = {Wed Apr 12 00:00:00 EDT 2017},
month = {Wed Apr 12 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevLett.118.159601

Citation Metrics:
Cited by: 3works
Citation information provided by
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  • Single crystals of Mg{sub 2}B{sub 24}C, a new boron-rich boridecarbide of magnesium, were synthesized as black needles and columns by reaction of the elements in Ta ampoules and BN crucibles at 1300 deg. C. The crystal structure was determined by X-ray diffraction (P-4n2, a=8.9391(13)A, c=5.0745(10)A, Z=2, 713 reflections, 64 variables, R{sub 1}(F)=0.0235, wR{sub 2}(I)=0.0591). It is closely related to 'tetragonal boron I' and can be described as a tetragonal rod packing of corner-linked B{sub 12} icosahedra with C and Mg atoms in the voids. Each B{sub 12} icosahedron has 2 B-C bonds and 10 exohedral bonds to other icosahedra, 2more » within the rod and 4x2 to neighbouring rods. The isolated C atoms are 4-fold coordinated forming distorted tetrahedra. Mg is placed on two crystallographically independent positions within the three-dimensional B{sub 12}C network. Mg{sub 2}B{sub 24}C is the first example for a compound related to 'tetragonal boron I' with a stoichiometric composition.« less
  • A Comment on the Letter by Bansil {ital et} {ital al}., Phys. Rev. Lett. 61, 2480 (1988).
  • The ternary rare-earth metal boride carbides RE{sub 15}B{sub 6}C{sub 20} (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-bar , Z=1, a=8.3431(8) A, b=9.2492(9) A, c=8.3581(8) A, {alpha}=84.72(1){sup o}, {beta}=89.68(1){sup o}, {gamma} =84.23(1){sup o} (R1=0.041 (wR2=0.10) for 3291 reflections with I{sub o}>2{sigma}(I{sub o})) for Pr{sub 15}B{sub 6}C{sub 20}, and a=8.284(1) A, b=9.228(1) A, c=8.309(1) A, {alpha}=84.74(1){sup o}, {beta}=89.68(1){sup o}, {gamma}=84.17(2){sup o} (R1=0.033 (wR2=0.049) for 2970 reflections with I{sub o}>2{sigma}(I{sub o})) for Nd{sub 15}B{sub 6}C{sub 20}. Their structure consists ofmore » 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 B{sub 2}C{sub 4} finite chains, disordered C{sub 3} entities and isolated carbon atoms, respectively. Structural and theoretical analyses suggest the ionic formulation (RE{sup 3+}){sub 15}([B{sub 2}C{sub 4}]{sup 6-}){sub 3}([C{sub 3}]{sup 4-}){sub 2}(C{sup 4-}){sub 2}.11e. 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 B{sub 2}C{sub 4} chains support the presence of a CBCCBC unit. Pr{sub 15}B{sub 6}C{sub 18} exhibits antiferromagnetic order at T{sub N}=7.9 K, followed by a meta-magnetic transition above a critical external field B>0.03 T. On the other hand, Nd{sub 15}B{sub 6}C{sub 18} is a ferromagnet below T{sub C}{approx}40 K. - Graphical abstract: The ternary rare-earth metal boride carbides RE{sub 15}B{sub 6}C{sub 20} (RE=Pr, Nd) were synthesized by co-melting the elements. They exist above 1270 K. 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 B{sub 2}C{sub 4} finite chains, disordered C{sub 3} entities and isolated carbon atoms, respectively. Structural and theoretical analyses suggest the ionic formulation (RE{sup 3+}){sub 15}([B{sub 2}C{sub 4}]{sup 6-}){sub 3}([C{sub 3}]{sup 4-}){sub 2}(C{sup 4-}){sub 2} 11e. Pr{sub 15}B{sub 6}C{sub 18} exhibits antiferromagnetic order at T{sub N}=7.9 K, followed by a meta-magnetic transition above a critical external field B>0.03 T. On the other hand, Nd{sub 15}B{sub 6}C{sub 18} is ferromagnetic below T{sub C}{approx}40 K.« less
  • Crystals of a new polar borate Na{sub 2}Ce{sub 2}[BO{sub 2}(OH)][BO{sub 3}]{sub 2} · H{sub 2}O were prepared by hydrothermal synthesis. The crystals are orthorhombic, a = 7.2295(7) Å, b = 11.2523(8) Å, c = 5.1285(6) Å, Z = 2, sp. gr. C2mm (Amm2), R = 0.0253. The formula of the compound was derived from the structure determination. The Ce and Na atoms are coordinated by nine and six O atoms, respectively. The Ce position is split, and a small amount of Ce is incorporated into the Na1 site with the isomorphous substitution for Na. The anionic moieties exist as isolatedmore » BO{sub 3} and BO{sub 2}(OH) triangles. The planes of the BO{sub 2}(OH) triangles with mm2 symmetry are parallel to the ab plane. The planes of the BO{sub 3} triangles with m symmetry are perpendicular to the ab plane and are rotated in a diagonal way. The splitting of the Ce positions and the polar arrangement of the BO{sub 2}(OH) triangles, water molecules, and Na atoms are observed along the polar a axis. The new structure is most similar to the new borate NaCa{sub 4}[BO{sub 3}]{sub 3} (sp. gr. Ama2), in which triangles of one type are arranged in a polar fashion along the c axis. Weak nonlinear-optical properties of both polar borates are attributed to the quenching of the second-harmonic generation due to the mutually opposite orientation of two-thirds of B triangles in the unit cell.« less