The Polar Phase of NaNbO: A Combined Study by Powder Diffraction, Solid-State NMR, and First-Principles Calculations.
A polar phase of NaNbO has been successfully synthesized using sol-gel techniques. Detailed characterization of this phase has been undertaken using high-resolution powder diffraction (X-ray and neutron) and Na multiple-quantum (MQ) MAS NMR, supported by second harmonic generation measurements and d...
| Published in: | Journal of the American Chemical Society Vol. 132; no. 25; pp. 8732 - 8747 |
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| Main Authors: | , , , , , |
| Format: | Article |
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American Chemical Society
6/30/2010
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| Subjects: | |
| Online Access: | View this record in EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=52271142&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 52271142 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 6/30/2010 vid: 132 iid: 25 pid: 997 pub: American Chemical Society artinfo: ui: 52271142 10.1021/ja101860r ppf: 8732 ppct: 15 formats: tig: atl: The Polar Phase of NaNbO: A Combined Study by Powder Diffraction, Solid-State NMR, and First-Principles Calculations. aug: au: Johnston, Karen E. Tang, Chiu C. Parker, Julia E. Knight, Kevin S. Lightfoot, Philip Ashbrook, Sharon E. affil: School of Chemistry and EaStCHEM, University of St. Andrews, St. Andrews, KY16 9ST, U.K. Diamond Light Source Ltd., Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, U.K. ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot, OX11 0QX, U.K. su: Sodium compounds Optical diffraction Nuclear magnetic resonance spectroscopy Particles (Nuclear physics) Second harmonic generation Colloids sug: subj: Sodium compounds Optical diffraction Nuclear magnetic resonance spectroscopy Particles (Nuclear physics) Second harmonic generation Colloids ab: A polar phase of NaNbO has been successfully synthesized using sol-gel techniques. Detailed characterization of this phase has been undertaken using high-resolution powder diffraction (X-ray and neutron) and Na multiple-quantum (MQ) MAS NMR, supported by second harmonic generation measurements and density functional theory calculations. Samples of NaNbO were also synthesized using conventional solid-state methods and were observed to routinely comprise of a mixture of two different polymorphs of NaNbO, namely, the well-known orthorhombic phase (space group Pbcm) and the current polar phase, the relative quantities of which vary considerably depending upon precise reaction conditions. Our studies show that each of these two polymorphs of NaNbO contains two crystallographically distinct Na sites. This is consistent with assignment of the polar phase to the orthorhombic space group P2ma, although peak broadenings in the diffraction data suggest a subtle monoclinic distortion. Using carefully monitored molten salt techniques, it was possible to eradicate the polar polymorph and synthesize the pure Pbcm phase. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2010 holdings: @attributes: islocal: N |
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