Investigation of phase transitions and vibrational spectrum of CsHSO4 superionic conductor lattice using the neutron scattering method

The results of elastic and inelastic neutron scattering studies on phase transitions and vibrational spectra in CsHSO4(CHS) superionic conductor at the IBR-2 pulsed reactor are reported. It is shown that in the 123-420 K temperature range there are three phases (3-2-1) in CHS crystal and only two phases (2-1) in partially deuterated Cs(Dsub(0.7)Hsub(0.3)SOsub(4)) crystal. Effect of the deuteration, moisture of a sample, and of the temperature regime on the character of phase transitions is investigated. Basing on a considerable change in the vibrational spectra of the lattice at the superionic phase transition a conclusion is drawn as to the statistical disorder of protons in the lattice at phase 1