Medium-range order in cesium borate glasses probed by double-resonance NMR.
Rotational-echo double-resonance NMR is used to probe the proximity of Cs+ network modifiers to network-forming boron in binary cesium borate glasses. Low- and high-alkali glasses show distinctly different dephasing curves, which indicate preferential association of Cs+ with four-co-ordinate boron ([4]degrees )B) at low-alkali contents only. Different [4]B sites within a given glass appear to be subject to the same 133Cs dipolar field, thus placing constraints on the possible assignments of multiple tetrahedral boron peaks to different types of medium-range order and guiding future structural modeling studies.
Aguiar
Pedro M
PM
Department of Chemistry, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2.
Kroeker
Scott
S