Si-O-Si angle is the most important parameter for the inter-tetrahedral structure.
What is moving in silica at 1 K? A computer study of the low-temperature anomalies
The most displaced tetrahedra shows variations of the O-Si-O angles of 2.7◦ which is nearly half of the overall equilibrium variation of intra-tetrahedral angles; see also .
What is moving in silica at 1 K? A computer study of the low-temperature anomalies
Double Tetrahedral Group For years, Ma and many others have advocated the use of the tetrahedral group T (cid:39) A4 to explain the large neutrino mixing angles.
Neutrino Mixing and the Double Tetrahedral Group
The limits on this part, as calculated by Keffer and Portis for AlN, are u = 0.380 to maintain equal nearest neighbour bond lengths and u = 0.372 to maintain equal four tetrahedral angles.
Relative stability of zincblende and wurtzite structure in CdX(X = S, Se, Te) series - A NMTO study
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