Results 81 to 90 of about 151 (135)

The Madelung Function of Elpasolites

Zeitschrift für Naturforschung B, 2000
Abstract Madelung Energy, Coulomb Interaction, Elpasolite For binary ionic compounds the Madelung energy can be calculated using the Madelung constant, the ionic charges and the next neighbour distance of the ions only. For ternary and higher systems the well-known standard formula cannot be applied, because the ionic charges and ...
Veit Marx, Bernd Hundhammer
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Elpasolite from hyperalkaline pegmatite of the Khibiny pluton, Kola Peninsula. Symmetry of elpasolite

Geology of Ore Deposits, 2008
Elpasolite, K2NaAlF6, has been found for the first time in a pegmatite related to peralkaline foid syenite at Mt. Koashva, Khibiny alkaline pluton, Kola Peninsula, Russia, as pale pink octahedral crystals up to 2 mm in size within cavities in the natrolite core of pegmatite in association with amicite, sodalite, aegirine, pectolite, catapleiite ...
I. V. Pekov, N. V. Chukanov, N. N. Kononkova, N. V. Zubkova, M. Kh. Rabadanov, D. Yu. Pushcharovsky   +5 more
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Specific heat of the elpasolite Pb2MgWO6

Physics of the Solid State, 1999
The specific heat of Pb2MgWO6 has been measured in the temperature interval 83–370 K. An anomaly in the specific heat associated with the phase transition at T 0=312.8K has been discovered. The thermodynamic parameters of the structural phase transition Fm3m-Pmcn have been determined.
I. N. Flërov, M. V. Gorev, Ph. Sciau
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Phase transitions in elpasolites (ordered perovskites)

Materials Science and Engineering Reports, 1998
Abstract Many compounds with general chemical formula A 2 BB′X 6 and with tolerance factor value ...
I N Flerov, M V Gorev, A Tressaud
exaly   +2 more sources

Prediction of new halo-elpasolites

Russian Journal of Inorganic Chemistry, 2016
We predicted elpasolites having the composition A2BCHal6 (A and C stand for different monovalent metals; B stands for trivalent metals; and Hal for F, Cl, or Br) that have not been obtained yet. Prediction was based on the data on properties of elements and simple halides only.
N. N. Kiselyova, A. V. Stolyarenko, V. V. Ryazanov, O. V. Sen’ko, A. A. Dokukin   +4 more
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Ferroelastic phase transitions in elpasolites

Ferroelectrics, 1985
The crystallography analysis of the rotation distortions in elpasolite type crystals1 showed that the structure has instability of high symmetry cubic phase (Go=O5h) in respect to rotations of the octahedra. The superposition of the two rotation types leads to different distorted phases.
I. N. Flerov, A. F. Bovina, V. N. Voronov, M. V. Gorev, S. V. Misjul, S. V. Melnikova, L. A. Shabanova   +6 more
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Entropy and the mechanism of phase transitions in elpasolites

Physics of the Solid State, 2001
The phase transitions in series of crystals with the general formulas A2BB’X6 (X=F, Cl, Br, or CN) and Pb2BB’O6 that belong to the elpasolite family (space group $$Fm\bar 3m$$ ) are analyzed.
I. N. Flerov, M. V. Gorev
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Development of an elpasolite planetary science instrument

2016 IEEE Nuclear Science Symposium, Medical Imaging Conference and Room-Temperature Semiconductor Detector Workshop (NSS/MIC/RTSD), 2016
Planetary gamma-ray and neutron spectroscopy from orbiting spacecraft has become a standard technique to measure distinctive composition and abundance signatures for key elements relevant to planetary structure and evolution. Previous instrumentation that has led to the discovery of the concentration of many elements including hydrogen (a strong ...
Suzanne F. Nowicki, Laura C. Stonehill, Daniel D. S. Coupland, Katherine E. Mesick   +3 more
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Crystal structure of Rb-elpasolite Rb2NaAlF6

Crystallography Reports, 2013
Single crystals of Rb2NaAlF6, the Rb analogue of the mineral elpasolite, are obtained in the NaF-Rb2CO3-Al2O3-Rb3PO4-H2O system under hydrothermal conditions, and their structure is determined by X-ray diffraction (R = 0.0188): a = 8.3087(1) A, space group \(Fm\bar 3m\), Z = 4, and ρcalcd = 3.88 g/cm3. The hypothesis that Rb elpasolite exists in nature
O. V. Yakubovich, G. V. Kiryukhina, O. V. Dimitrova   +2 more
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The Synthesis and Structures of Elpasolite Halide Scintillators

MRS Proceedings, 2009
AbstractLow-cost, high-performance gamma-ray spectrometers are urgently needed for nonproliferation and homeland security applications. Available scintillation materials fall short of the requirements for energy resolution and sensitivity at room temperature.
Pin Yang, F. Patrick Doty, Mark A. Rodriguez, Margaret R. Sanchez, Xiaowong Zhou, Kanai S. Shah   +5 more
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