Adiabatic bond charge model

Weber, W. (1977) Adiabatic bond charge model for the phonons in diamond. Phys. Rev. B 15, 4789-803. 

The temperature dependence of the spin-lattice relaxation time corresponding to the inelastic scattering of phonons by the Ge quadrupole moment in Ge single crystals is calculated in the framework of the adiabatic bond charge model. The results obtained agree with the experimental data. " ... 

In the bond charge model, the effect of the metal-like binding is described by central forces between nearest-neighbour ions while the covalent bonding is described by interactions involving the BC s [4.51,52]. In the adiabatic bond charge model of WEBER [4.17,18], the constraint that the BC s are fixed on the midway positions between the atoms is removed. Instead, they are allowed to move adiabatically like the electronic shells in the shell... 

An adiabatic bond charge model for covalent crystals has also been put forward by JOHNSON [4.53] and by JOHNSON and MOORE [4.54] in contrast to WEBER S model, all interactions in Johnsons model are purely electrostatic. Finally, it should be mentioned that bond charge models have also been used to study the vibrations of diatomic and polyatomic molecules [4.55,56]. 

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