| Journal: | Revista mexicana de física |
| Database: | PERIÓDICA |
| System number: | 000363622 |
| ISSN: | 0035-001X |
| Authors: | Jurado, J.F1 Vargas Hernández, C1 Vargas, R.A2 |
| Institutions: | 1Universidad Nacional de Colombia, Departamento de Física y Química, Bogotá. Colombia 2Universidad del Valle, Departamento de Física, Cali, Valle del Cauca. Colombia |
| Year: | 2012 |
| Season: | Oct |
| Volumen: | 58 |
| Number: | 5 |
| Pages: | 411-416 |
| Country: | México |
| Language: | Inglés |
| Document type: | Artículo |
| Approach: | Analítico, teórico |
| English abstract | We have studied the high-temperature phase transition (HTPT) of crystalline potassium and ammonium dehydrogen phosphates and solid solutions of them with composition (1-x) KH2 PO4 + x NH4 H2 PO4 (KADPx, for x =0.0, 0.1, 0.2, 0.3, 0.4, 0.6 and 1.0), by means of X-ray diffraction analysis at room temperature and in situ Raman spectroscopy as function of temperature. Analysis of the Raman spectra made it possible to monitor the temperature dependence of vibrational bands associated to structural changes taking place during a proposed partial dehydration reaction that starts to take place at a characteristic temperature Tp and tends to increase above it. This assignment is supported using characteristic vibrational bands of phosphates and polyphosphates (produced as a consequence of the partial dehydration reaction of the crystals above Tp). The presence of the polyphosphate vibrational bands assigned to the stretch vibration of its PO2 species (at about 1120 cm_1for pure KDP) accompanied by a broad band assigned to P-O-P backbone vibrations (at about 713 cm_1for pure KDP) [14] become evident at temperature higher than Tp depending on the composition of KADPx |
| Disciplines: | Física y astronomía |
| Keyword: | Física de materia condensada, Difracción de rayos X, Cristales iónicos, Estados vibratorios, Raman |
| Keyword: | Physics and astronomy, Condensed matter physics, X-ray diffraction, Ionic crystals, Vibrational states, Raman |
| Full text: | Texto completo (Ver PDF) |
