Published February 2004 | Version v1
Journal article Metadata-only

Calorimetry and electrophysical properties of chromite GdMgCr2O5.5

Creators

  • 1. Minesterstvo Obrazovaniya i Nauki Respubliki Kazakhstan, Inst. Fotokhimii, Karaganda (Kazakhstan)

Description

Chromite GdMgCr2O5.5 was synthesized by solid-phase technology. According to X-ray phase analysis data the compound is crystallized in tetragonal crystal system with unit cell parameters as follows: a=10.79, c=16.54 A, Z=16. Abrupt anomalous jumps at 448 and 498 K were revealed in heat capacity temperature dependence measured in the range of 298.15-673 K, the jumps stemming from second-order phase transitions. The anomalies mentioned agree well with specific features of temperature dependence of dielectric permittivity and electric resistance of the chromite studied. The heat capacity temperature dependence permitted calculation of thermodynamic functions of the chromite in the rage of 298.15-673 K

Abstract (Russian)

Методом твердофазного синтеза получен GdMgCr2O5.5. По данным рентгенофазового анализа соединение кристаллизуется в тетрагональной сингонии с параметрами элементарной ячейки: a=10.79, c=16.54 A, Z=16. На измеренной в интервале 298.15-673 K температурной зависимости теплоемкости обнаружены аномальные скачки при 448 и 498 K, которые связяны с фазовыми переходами второго рода. Указанные аномалии хорошо согласуются с особенностями температурных зависимостей диэлектрической приницаемости и электросопротивления изученного хромита. На основе температурной азвисимости теплоемкости рассчитаны термодинамические функции хромита в интервале 298.15-673 K

Additional details

Additional titles

Original title (Russian)
Калориметрия и электрофизические свойства хромита GdMgCr

Publishing Information

Journal Title
Zhurnal Neorganicheskoj Khimii
Journal Volume
49
Journal Issue
2
Journal Page Range
p. 304-308
ISSN
0044-457X
CODEN
ZNOKAQ

INIS

Country of Publication
Russian Federation
Country of Input or Organization
Russian Federation
INIS RN
36084565
Subject category
S37: INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY;
Descriptors DEI
CHEMICAL PREPARATION; CHROMITES; ELECTRIC CONDUCTIVITY; ENTHALPY; ENTROPY; GADOLINIUM COMPOUNDS; LATTICE PARAMETERS; MAGNESIUM COMPOUNDS; PERMITTIVITY; PHASE TRANSFORMATIONS; SPECIFIC HEAT; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0273-0400 K; TEMPERATURE RANGE 0400-1000 K; TETRAGONAL LATTICES
Descriptors DEC
ALKALINE EARTH METAL COMPOUNDS; CHROMIUM COMPOUNDS; CRYSTAL LATTICES; CRYSTAL STRUCTURE; DIELECTRIC PROPERTIES; ELECTRICAL PROPERTIES; OXYGEN COMPOUNDS; PHYSICAL PROPERTIES; RARE EARTH COMPOUNDS; SYNTHESIS; TEMPERATURE RANGE; THERMODYNAMIC PROPERTIES; TRANSITION ELEMENT COMPOUNDS

Optional Information

Notes
10 refs., 3 figs., 4 tabs.