Current time in Korea 20:49 Oct 22 (Sun) Year 2017 KCS KCS Publications
KCS Publications
My Journal Log In Register
HOME > Search > Browsing(BKCS) > Archives

Bulletin of the Korean Chemical Society (BKCS)

ISSN 0253-2964(Print)
ISSN 1229-5949(Online)
Volume 30, Number 3
BKCSDE 30(3)
March 20, 2009 

 
Title
Solid-state MAS NMR Investigation on the Local Structures
of xV2O5-B2O3-yNa2O Glasses
Author
Sun Ha Kim, Oc Hee Han*, Jae Pil Kang, Seung Ki Song
Keywords
Glass structure, Nuclear magnetic resonance, MAS NMR
Abstract
The local structures of the boron and vanadium sites in the ternary glass xV2O5-B2O3-yNa2O were studied by 11B and 51V magic angle spinning (MAS) nuclear magnetic resonance (NMR). With increasing x, the mole ratios of the BO3 and BO4 structures were enhanced, as were the quadrupole asymmetry parameters for the BO3 structures, while the quadrupole coupling constants for the sites were reduced. However, the opposite trends were observed with increasing y, implying that V2O5 and Na2O play opposite roles. The VO4, VO5 and VO6 structures with all oxygens bonded to the vanadium neighbors were identified. Vanadiums bonded to the greater number of oxygens were more populated at higher contents of Na2O and V2O5. In addition, the VO4 structures with at least one oxygen bonded to boron instead of vanadium were detected at low Na2O contents. The electron densities of various vanadium oxide structures were affected by the weight densities and vanadium ion densities. The VO4 structures were more likely to be vanadium oxide structures right next to V4+ ions.
Page
608 - 612
Full Text
PDF