Determination of the bond-angle distribution in vitreous B2O3 by 11B double rotation (DOR) NMR spectroscopy

✍ Scribed by I. Hung; A.P. Howes; B.G. Parkinson; T. Anupõld; A. Samoson; S.P. Brown; P.F. Harrison; D. Holland; R. Dupree

• Book ID: 104030429
• Publisher: Elsevier Science
• Year: 2009
• Tongue: English
• Weight: 532 KB
• Volume: 182
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2009.06.025

✦ Synopsis

The B-O-B bond angle distributions for both ring and non-ring boron sites in vitreous B 2 O 3 have been determined by 11 B double rotation (DOR) NMR and multiple-quantum (MQ) DOR NMR. The [B 3 O 6 ] boroxol rings are observed to have a mean internal B-O-B angle of 120.070.71 with a small standard deviation, s R ¼ 3.270.41, indicating that the rings are near-perfect planar, hexagonal structures. The rings are linked predominantly by non-ring [BO 3 ] units, which share oxygens with the boroxol ring, with a mean B ring -O-B non-ring angle of 135.170.61 and s NR ¼ 6.770.41. In addition, the fraction of boron atoms, f, which reside in the boroxol rings has been measured for this sample as f ¼ 0.7370.01.