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Updated: Jun 3, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
First-principles investigation of the relation between structural and NMR parameters in vitreous GeO2
Mikhail Kibalchenko1, Jonathan R Yates, Alfredo Pasquarello
1TCM Group, Cavendish Laboratory, University of Cambridge, Cambridge CB3 0HE, UK. mk531@cam.ac.uk
Abstract:
NMR parameters of (73)Ge and (17)O in vitreous GeO(2) and quartz GeO(2), including the isotropic shifts, the quadrupole coupling constants C(Q), and the electric-field-gradient asymmetry parameters η, are determined through density functional calculations. Clear correlations are established between (73)Ge shifts and the mean of the four neighboring Ge-O-Ge bond angles, and between C(Q) and η parameters of (17)O and the local Ge-O-Ge angle. Available experimental data for C(Q) and the corresponding established correlation are used to extract the value of 135° for the average Ge-O-Ge angle in vitreous GeO(2). The features of the Ge-O-Ge bond angle distribution of vitreous GeO(2) derived in this work are consistent with those inferred from other experimental probes.
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