Phase transitions in the Mitsui model

Abstract

In this paper, phase transitions in the Mitsui model without longitudinal field but with a transverse one are investigated in the mean field approximation. The one-to-one correspondence has been established between this model and the two-sublattice Ising-type model with longitudinal and transverse fields. Phase diagrams and diagrams of existence of the ferroelectric phase are constructed. In the case Ω = 0 (Ω is the transverse field), a simple analytical expression for the tricritical temperature and the condition of existence of the tricritical point are obtained. For Ω = 0, systems of equations for the tricritical point and for the condition of its existence are written.

Mitsui model with diagonal strains: A unified description of external pressure effect and thermal expansion of Rochelle salt NaKC_4H_4O_6·4H_2O

“…The phase diagram of the conventional (undeformable) Mitsui model in the (ā,b) plane [36][37][38] shows the regions with different numbers and types of the phase transitions; its topology is not changed by inclusion of the shear strain ε 4 . It has been found that only in a very narrow region of the (ā,b) plane, the system undergoes two second order phase transitions with the intermediate ferroelectric phase.…”

Dielectric, piezoelectric, elastic and thermal properties of Rochelle salt NaKC4H4O6 · 4H2O

“…Пiзнiше фазовi дiаграми для моделi Мiцуї докладнiше були вивченi в роботах [19,20]. Однак лише в працi [21] побудовано повну фазову дiаграму моделi Мiцуї й вивчено її змiни пiд впливом тунелювання.…”