Determination of the bond-angle distribution in vitreous B{sub 2}O{sub 3} by {sup 11}B double rotation (DOR) NMR spectroscopy
- Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)
- National Institute for Chemical Physics and Biophysics, Akadeemia Tee 23, Tallinn (Estonia)
The B-O-B bond angle distributions for both ring and non-ring boron sites in vitreous B{sub 2}O{sub 3} have been determined by {sup 11}B double rotation (DOR) NMR and multiple-quantum (MQ) DOR NMR. The [B{sub 3}O{sub 6}] boroxol rings are observed to have a mean internal B-O-B angle of 120.0+-0.7 deg. with a small standard deviation, sigma{sub R}=3.2+-0.4 deg., indicating that the rings are near-perfect planar, hexagonal structures. The rings are linked predominantly by non-ring [BO{sub 3}] units, which share oxygens with the boroxol ring, with a mean B{sub ring}-O-B{sub non-ring} angle of 135.1+-0.6 deg. and sigma{sub NR}=6.7+-0.4 deg. In addition, the fraction of boron atoms, f, which reside in the boroxol rings has been measured for this sample as f=0.73+-0.01. - Graphical abstract: Connectivities and B-O-B bond angle distributions of ring and non-ring boron atoms in v-B{sub 2}O{sub 3} have been determined by {sup 11}B double rotation (DOR) NMR, multiple-quantum (MQ) DOR NMR and spin-diffusion DOR. Near-perfect planar, hexagonal [B{sub 3}O{sub 6}] boroxol rings are shown to be present. Display Omitted
- OSTI ID:
- 21370570
- Journal Information:
- Journal of Solid State Chemistry, Vol. 182, Issue 9; Other Information: DOI: 10.1016/j.jssc.2009.06.025; PII: S0022-4596(09)00284-9; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0022-4596
- Country of Publication:
- United States
- Language:
- English
Similar Records
Molecular dynamics simulation of local structure and vibrational spectrum of uranyl (UO{sub 2}){sup 2+} in vitreous B{sub 2}O{sub 3}.
Calculation of the structure, vibrational spectra, and polarizability of boroxine, H sub 3 B sub 3 O sub 3 , a model for boroxol rings in vitreous B sub 2 O sub 3