The work investigates the applicability of the Keating Model to estimation of the crystal lattice dynamics with the atomic coordination different from that of tetrahedral. The general model statement is considered in view of the long-range pattern of Coulomb interaction, software support of estimations with total consistency and accuracy assessment in terms of test systems to be standard for the Keating Model, and calculation results are given with the analysis of the crystal phonon spectrum structured like the mineral salt and fluorite. It is shown that the best choice of the model parameters will result in values for compounds of the structure above that are well consistent with experimental data, including acoustic vibration frequency range, where the Keating Model normally results in the increased values thereof.

A method to unfold phonon band structure is proposed which is as simple and general as those used in the electronic structure calculations. It is achieved using continuous Bloch representation of vibrational eigenmodes. The results of lattice dynamics calculations for perfect and defect diamond as well as for calcium fluorite demonstrate good accuracy and performance of the approach.

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