Electrostatic energy Madelung constants

The electrostatic (Madelung) part of the lattice energy (MAPLE) has been employed to define Madelung potentials of ions in crystals (Hoppe, 1975). MAPLE of an ionic solid is regarded as a sum of contributions of cations and anions the Madelung constant. A, of a crystal would then be the sum of partial Madelung constants of cation and anion subarrays. Thus,... 

It was noted in Chapter 4 that the Madelung constant of a structure may be expressed in various ways. The way that is conceptually simplest in terms of the Bom-Lande equation is the simple geometric factor. A, such that when combined with the true ionic charges, Z and Z, the correct electrostatic energy is formulated. It was noted that some workers have favored using another constant, A. combined with the highest common factor of Z and Z. Z -... 

The crystal lattice energy can be estimated from a simple electrostatic model When this model is applied to an ionic crystal only the electrostatic charges and the shortest anion-cation intermiclear distance need be considered. The summation of all the geometrical interactions be/Kveeti the ions is called the Madelung constant. From this model an equatitWjor the crystal lattice energy is derived ... 

Madelung constant — is the factor by which the ionic charges must be scaled to calculate the electrostatic interaction energy of an ion in a crystal lattice with given... 

The determination of the Madelung constant for a crystal structure requires the evaluation of electrostatic self-potentials of the structure. Any lattice energy can also be expressed using lattice site self-potentials (which is what Ewald actually calculated) ... 

Macromolecule - A molecule of high relative molecular mass (molecular weight), the structure of which essentially comprises the multiple repetition of units derived, actually or conceptually, from molecules of low relative molecular mass. [8] Madelung constant - A constant characteristic of a particular crystalline material which gives a measure of the electrostatic energy binding the ions in the crystal. 

Here Madelung the electrostatic energy of the crystal, e the electronic charge multiplied by the valence of the ions of the structure, r a measure of the lattice constants of the crystal, and A the Madelung constant, which depends only on the crystal structure. 

Madelung constant A constant, denoted a, which appears in calculations of the cohesive energy of ionic crystals when the electrostatic interactions between ions in a lattice are summed. The Madelung constant is dimensionless and is a characteristic of the specific crystal structure. It is named for E. Madelung who introduced it in 1918. 

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