Encyclopedia of Glass Science, Technology, History, and Culture. Группа авторов
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a Common coordination numbers; others may occur. Five‐coordinate states are also known for many cations listed with 4 and 6 coordination (e.g. Al, Si, Ti, Ni), which have intermediate radii and field strengths.
b Cation field strength, valence divided by square of cation–oxygen distance, with the radius of the latter taken as 1.36 Å, the typical value for three‐coordinated O.
c Pauling electronegativity, from Pauling, L. (1970). General Chemistry. San Francisco: W.H. Freeman.
d “Network former” description is generally most appropriate for lower coordination numbers.
e Lone‐pair electronic structure may lead to lower coordination than expected from radius.
f Radii for high spin electronic state.
g Effective ionic radius, from Shannon, R.D. (1976). Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Cryst. A32, 751–767.
Table A.2 S.I. units and physical constants.
Symbol | Value | Unit | |
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