Dielectric, DSC and Raman studies of the phase transitions in NH4(HSO4)(0.45)(H2PO4)(0.55) mixed crystals

Authors
Bouattour, S Mhiri, T Kolsi, AW Romain, F
Citation
S. Bouattour et al., Dielectric, DSC and Raman studies of the phase transitions in NH4(HSO4)(0.45)(H2PO4)(0.55) mixed crystals, PHASE TRAN, 70(1), 1999, pp. 19-28
Citations number
14
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHASE TRANSITIONS
ISSN journal
01411594 → ACNP
Volume
70
Issue
1
Year of publication
1999
Part
A
Pages
19 - 28
Database
ISI
SICI code
0141-1594(1999)70:1<19:DDARSO>2.0.ZU;2-W
Abstract
Investigation of the system NH4HSO4-NH4H2PO4 has led to the discovery of th e new solid solution NH4(HSO4)(x)(H2PO4)(1-x) (x = 0.45) which has been pre pared by slow evaporation from aqueous solution at room temperature. This m ixed crystal is orthorhombic. Differential scanning calorimetric (DSC), die lectric permittivity at different Frequencies, and Raman studies in the ran ge 15-3600 cm(-1) at various temperatures show two phase transitions at 117 and 155 K, probably of second order.