A theory is developed for structural phase transitions in the layer metallic compound 1 T-VSe 2 , taking into account the interlayer interaction of charge density waves (CDWs). Three-dimensional ordering of CDWs is investigated, and with information about the strength of diffuse x-ray scattering a conclusion is drawn regarding the structure of the incommensurate phases
Neutron diffraction by polycrystalline samples was used to determine the magnetic order in Re 2 BaCuO 5 cuprates, where Re = Dy, Ho, Er, Tm, and Yb. The investigation was carried out at various temperatures. The crystal structure parameters were determined in the paramagnetic phase. All the compounds exhibited different antiferromagnetic structures. Spin-reorientation transitions were observed for Dy 2 BaCuO 5 and Ho 2 BaCuO 5 when temperature was varied
The lattice reflection spectra of Cd 1−x Hg x Te alloys are analyzed in the two-mode approximation for the vibrational spectrum of quasibinary alloys in terms of CdTe- and HgTe-like vibrations. The composition dependences of frequencies of the TO and LO modes of CdTe-like and HgTe-like vibrations are obtained at temperatures 25, 85, and 300 K. A comparison is made of the information derived from the two-mode and quasimolecular approximations
