Abstract
Neutron powder thermodiffractometry has been used to determine the phase
diagram of LiK1-x RbxSO4 mixed crystals (x less than or equal to 0.50),
between 50 and 800 K. We observed that, in this temperature range, these
crystals undergo practically the same sequence of phase transitions as
pure LiKSO4 crystal. The main effects of the presence of rubidium ions
in the potassium sites are seen in the variations of the critical
temperatures and in the smearing of the first order transitions. We
observed the narrowing of the region of the room temperature hexagonal
phase with increasing Rb concentration. Its upper limit temperature
decreases, while the lower one increases, favoring the trigonal phase.
The low-temperature ferroelastic phase is absent for crystals with Rb
concentration higher than c.a. 0.30. (C) 1998 Elsevier Science Ltd. All
rights reserved.
Users
Please
log in to take part in the discussion (add own reviews or comments).