Effects of interlayer interactions on charge-density waves in the2H−TaSe2structure

Interlayer interactions are added to a model used previously by the authors to discuss the possible distinct commensurate charge-density-wave phases of the $2H-\mathrm{T}\mathrm{a}{\mathrm{Se}}_2$ structure; these interactions are found to determine the stacking of the layers, to give rise to an anisotropy of the energy of the discommensurations occurring in the orthorhombic phases, and to affect the Se NMR and Ta Mössbauer spectra. The ion displacements determined by the model are given in parametrized form for both the hexagonal and orthorhombic phases, and the order of the normal-incommensurate transition is determined.