The Central Role of Broken Bond-Bending Constraints in Promoting Glass Formation in the Oxides
The Central Role of Broken Bond-Bending Constraints in Promoting Glass Formation in the Oxides
复制标题
断裂的键弯曲约束在促进氧化物中玻璃形成中的核心作用
DOI:
10.1126/science.266.5189.1355
复制
发表时间:
1994
期刊:
影响因子:
56.9
通讯作者:
P. Boolchand
中科院分区:
文献类型:
--
作者:
M. Zhang;P. Boolchand
A glass network of N atoms with n1 of the atoms with a coordination number of 1, and m2 of the atoms with a coordination number of 2 about which the bond-angle constraint is broken, will in general display a stiffness threshold (rigidity percolation threshold) when the average coordination increases to a critical value (r)c = 2.4 – 0.4 (n1 – m2)/N. Silica and sodium tellurate glasses provide model examples for which this general relation predicts the observed rigidity percolation threshold; this relation predicts the percolation threshold only if one includes broken bond-bending constraints due to bridging oxygen in the former network and nonbridging oxygen in the latter network. The rigidity percolation threshold in (Na2O)x,(TeO2)1–x glasses observed to occur near x ≃ 0.18 in tellurium-125 Lamb-M�ssbauer factor measurments.