Repozytorium

The phase situation and ferroelectric properties in the mixed crystals [4-NH2PyH][SbCL4(1x)Br4x].

Autorzy

Maciej Wojtaś

Ryszard Jakubas

J. Zaleski

Grażyna Bator

Jan Baran

Rok wydania

2008

Czasopismo

Journal of Molecular Structure

Numer woluminu

887

Strony

262-268

DOI

10.1016/j.molstruc.2008.02.050

Kolekcja

Naukowa

Język

Angielski

Typ publikacji

Artykuł

Streszczenie

The group of mixed crystals of general formula: [4-APyH][SbCl4(1−x) Br4x] with x ranging from 0 to 1 was studied by means of differential scanning calorimetry, dilatometry and dielectric spectroscopy. The ferroelectric properties are preserved for mixed crystals with replacement fraction, x, less than 0.30. Moreover, such a substitution of the chlorine atoms by the bromine ones significantly lowers the temperature of the structural phase transition shifting it from 240 K for pure [4-APyH][SbCl4] to about 185 K for the mixed crystals richer in bromine. The dielectric relaxation process exhibited by the mixed crystal with x = 0.90 in the radio-frequency region was analyzed and the activation energy was estimated (Ea = 18 kJ/mol). Additional measurements of single crystals X-ray diffraction and powder IR and Raman spectroscopy were performed. On the basis of the experimental results the phase diagram for mixed crystals has been proposed.

Słowa kluczowe

4-Aminopyridinium, Halogenoantimonates(III), Dielectric spectroscopy, Raman spectroscopy

Adres publiczny

http://doi.org./ 10.1016/j.molstruc.2008.02.050

Strona internetowa wydawcy

http://www.elsevier.com

Podobne publikacje
1998

Raman studies of ferroelectric phase transition in [NH2(CH3)]3Sb2Cl9(DMACA).

Bator Grażyna , Jakubas Ryszard, Lefebvre J., Guinet Y.