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Effect of hydrostatic-pressure on modulated phases in Rb2ZnBr4 / K. PARLINSKI [et al.]> // Phys. Rev. B. - 1992. - Vol. 46, Is. 1. - P. 106-114, DOI 10.1103/PhysRevB.46.106. - Cited References: 36
. - ISSN 0163-1829РУБ Physics, Condensed Matter Рубрики: INCOMMENSURATE PHASES NEUTRON-SCATTERING X-RAY COMMENSURATE TRANSITIONS EVOLUTION MODEL WAVE Аннотация: Neutron-diffraction studies on modulated Rb2ZnBr4, carried out under hydrostatic pressure, revealed two new commensurate phases characterized by wave vectors q = 2/7b* and q = 1/4b*, respectively. The first order phase transition between them is revealed by the coexistence of two distinct peaks in the diffraction pattern. The observed pressure-temperature phase diagram contains: the above-mentioned phases, the ferroelectric commensurate phase q = 1/3, and a region characterized by wave-vector values in the interval q = 2/7-1/3. In this region the modulation wave vector exhibits stepwise behavior as a function of pressure, but remains nearly constant iii temperature runs. We have found in this region a characteristic memory effect in which two temperature runs performed at the same pressure lead to two different modulation wave-vector values, while only the thermal history of the sample is different in the two runs. At ambient pressure we confirm the presence of a multipeaked diffraction pattern just above the lock-in transition to the commensurate q = 1/3 phase. At 122 K the phase transition from the 1/3 phase to the 1/4 phase is detected in pressure scans. The transition mechanism involves the q = 2/7 phase, at least as a metastable intermediate phase.
WOS, Scopus Держатели документа: INST NUCL PHYS,PL-31342 KRAKOW,POLAND LV KIRENSKY PHYS INST,KRASNOYARSK 660036,USSR ИФ СО РАН Institut Laue-Langevin, 156X Centre de Tri, 38042 Grenoble, France Institute of Nuclear Physics, ul. Radzikowskiego 152, 31-342 Cracow, Poland L. V. Kirensky Institute of Physics, 660036 Krasnoyarsk, Russian Federation Institut f?r Kristalographie, Rheinisch-Westfalische Technische Hochschule Aachen, Aachen, Germany Institut f?r Festkorperforschung, Kernforschungsanlage J?lich G.m.b.H., J?lich D-5170, Germany Доп.точки доступа: PARLINSKI, K.; CURRAT, R.; VETTIER, C.; ALEKSANDROVA, I. P.; Александрова, Инга Петровна; ECKOLD, G. } Найти похожие
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