Analysis of Electronic Polarizabilities in Ionic Crystals

Abstract

The existing sets of additive electronic polarizabilities for alkali halides and alkaline earth chalcogenides are examined by evaluating the high frequency electronic dielectric constants and presenting a comparison with experimental data. The crystalline state values of polarizabilities are also compared with free ion values. Various physical effects responsible for changing the values of polarizabilities in the crystalline state are discussed. The differences in free state and crystalline state polarizabilities are investigated in terms of the classical model due to Havinga and quantum mechanical model due to Yamashita and Kurosawa.Existierende Sitze der additiven elektronischen Polarisierbarkeiten fur Alkalihalogenide und Alkalierdchalkogenide werden durch Berechnung der elektronischen Hochfrequenzdielektrizitatskonstanten und Vergleich mit experimentellen Werten untersucht. Die Werte der Polarisierbarkeiten des Kristallzustands werden auch mit den Werten der freien Ionen verglichen. Verschiedene physikalische Effekte, die fur die Anderung der Werte der Polarisierbarkeiten im kristallinen Zustand verantwortlich sind, werden diskutiert. Die Unterschiede der Polarisierbarkeiten des freien und des kristallinen Zustands werden mit dem klassischen Modell von Havinga und dem quantenmechanischen Modell von Yamashita und Kurosawa untersucht.

Features of electronic polarizability and approach to unique properties in tellurite glasses

“…A quantitative measure of cation-anion interaction is given by the so-called interionic interaction parameter A, which represents the charge overlapping of the negative ion with its nearest positive neighbor for a chosen cation-anion pair. 27,33 In the case of oxides, the parameter A correlates with a reduction in the polarizability of oxide ion when placed in oxide glass network with respect to the free ion polarizability due to interaction inside. The interionic interaction parameter, therefore, means the degree of the overlapping between O2p and cation valence orbitals in oxides, indicating the chemical bond strength of cation-oxide ion pairs.…”

Interionic Interactions, Electronic Polarizability and Optical Basicity of Oxide Glasses.

“…Recently Dimitrov and Komatsu4) have evaluated the values of parameter A for numerous simple oxides based on the approach deve loped in Ref. 3). It was found that in the case of simple oxides the parameter A represents the interionic interac tion between 2p-electron cloud of the oxide ion and the valence cloud of the cation in respect to form a chemical bond.…”

Characterization and optical absorption studies of VO2+:Li2O–K2O–Bi2O3–B2O3 glass system

“…It correlates with reducing the polarizability of negative ion placed in a crystal lattice in respect to the free-ion polarizability. Dikshit and Kumar based on the theory proposed by Yamashita and Kurosawa derived an expression for the calculation of the interaction parameter A for a given cation-anion pair [41] …”