کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1329410 1500074 2016 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The low-temperature structural behavior of sodium 1-carba-closo-decaborate: NaCB9H10
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی معدنی
پیش نمایش صفحه اول مقاله
The low-temperature structural behavior of sodium 1-carba-closo-decaborate: NaCB9H10
چکیده انگلیسی


• Two T-dependent ordered structures of Na(1-CB9H10) were determined by XRD.
• The lower-T monoclinic to higher-T orthorhombic transition occurs from 210 to 240 K.
• The main structural differences involve changes in the canting of the CB9H10− anions.
• DFT and neutron vibrational spectroscopy corroborate the lower-T monoclinic structure.
• The results are important for understanding the nature of this superionic conductor.

Two ordered phases of the novel solid superionic conductor sodium 1-carba-closo-decaborate (NaCB9H10) were identified via synchrotron x-ray powder diffraction in combination with first-principles calculations and neutron vibrational spectroscopy. A monoclinic packing of the large ellipsoidal CB9H10− anions prevails at the lowest temperatures, but a first-order transformation to a slightly modified orthorhombic packing is largely complete by 240 K. The CB9H10− anion orientational alignments and Na+ cation interstitial sitings in both phases are arranged so as to minimize the cation proximities to the uniquely more positive C-bonded H atoms of the anions. These results provide valuable structural information pertinent to understanding the relatively low-temperature, entropy-driven, order-disorder phase transition for this compound.

Ordered monoclinic and orthorhombic NaCB9H10 phases were determined by XRD and DFT computations and corroborated by neutron vibrational spectroscopy.Figure optionsDownload as PowerPoint slide

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Solid State Chemistry - Volume 243, November 2016, Pages 162–167
نویسندگان
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