English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Qualitative properties of the electronic band structure of a KCl crystal are used to derive a simple two-parameter model for the correlation function c(q, q') which arises in the theory of lattice dynamics. This function relates the adiabatic deformation of the electronic band structure to the vibration of the ion cores. Expressions for the dynamical matrices are derived. The model is ready for a direct computer evaluation of the phonon frequencies to test its validity.

A New Model for the Lattice Dynamics of Alkali Halides