Incorporation of Ga into the structure of Ge–Se glasses

Local motifs in GeS2–Ga2S3 glasses

“…Ge and Ga atoms were found to be fourfold coordinated [21,31,[33][34][35]. The average coordination number of selenium atoms was found to be higher than two in several studies [21,32,34], but twofold coordinated Se-atoms were reported by Golovchak et al [33].…”

“…The chemically ordered network model seems to be more or less valid in these compounds as reported in Refs. [31,35,33], but significant amount of M-M bonds were found even in Se-rich systems by Pethes et al [21]. The Ge-Ge, Ge-Ga and Ga-Ga bonds are hardly distinguishable by Raman measurements, but EXAFS measurements combined with diffraction investigations and RMC suggest that Ge-Ga bonds are preferred among the M-M bonds in these glasses.…”

“…Ge-Ga-Se systems were investigated by several groups and methods, for example by Raman scattering [31][32][33][34], X-ray diffraction and IR spectroscopy [35], X-ray photoelectron spectroscopy (XPS) [32,33], EXAFS [33], NMR spectroscopy [34], neutron diffraction and EXAFS measurement combined with reverse Monte Carlo (RMC) simulation technique [21]. Ge and Ga atoms were found to be fourfold coordinated [21,31,[33][34][35].…”

Structure and properties of off-stoichiometric Ba–Ga–Ge selenide glasses

“…In this network, Ga and Ge both adopt four-fold coordination, regardless of composition, while Se primarily adopts two-fold coordination [41,46]. The concentration of homopolar Ge-Ge bonds in Se-deficient BGGS ± Se glasses with z b 0 decreases upon addition of Se and becomes negligible in the stoichiometric composition with z = 0, as indicated by the intensities of the Raman band near 175 cm −1 and of the low-frequency component in the 77 Se MAS NMR spectra near 250 ppm (Figs.…”

Microhardness and optical property of chalcogenide glasses and glass‐ceramics of the Sn–Sb–Se ternary system

“…The weak Van der Waals’ force between layers leads to the relatively poorer mechanical property and thermal stability of ChGs than those of oxide glasses, thereby limiting the applications of ChGs . The mechanical property of ChGs can be improved by incorporating group IV and V metallic elements with high coordination number to cross‐link the network structure of ChGs. However, the detailed relationship between the mechanical property (especially microhardness) and the cross‐linking degree of the ChG network, which can be quantified using a fundamental metric called mean coordination number (MCN), has rarely been reported .…”