Stress/Pressure-Stabilized Cubic Polymorph of Li3Sb with Improved Thermoelectric Performance

Author(s):  
Mujde Yahyaoglu ◽  
Thomas Soldi ◽  
Melis Ozen ◽  
Christophe Candolfi ◽  
G. Jeffrey Snyder ◽  
...  

Li3Sb has two polymorphs crystallizing in a face-centered cubic cell (c-Li3Sb; BiF3 structure type; space group Fm¯3m) and in a hexagonal unit cell (h-Li3Sb; Na3As structure type; space group P63/mmc)....

1994 ◽  
Vol 9 (2) ◽  
pp. 146-147 ◽  
Author(s):  
C. Colbeau-Justin ◽  
A. Elfakir ◽  
M. Quarton

A new titanate K2ZnTiO4 has been synthesized by solid-state reaction. This compound is isostructural with K2ZnGeO4, space group Pca21, Z=8. Unit-cell parameters were determined: a=11.3352(6) Å, b=5.6352(5) Å, c=16.0125(13) Å, and V=1022.8(3) Å3. Powder diffraction data are reported.


2017 ◽  
Vol 46 (21) ◽  
pp. 6835-6838 ◽  
Author(s):  
Weiwei Xie ◽  
Michał J. Winiarski ◽  
Tomasz Klimczuk ◽  
R. J. Cava

A trigonal–tetragonal phase transition in SrMn2P2is proposed and confirmed experimentally under high pressure. At ambient pressure, SrMn2P2crystallizes in the primitive trigonal La2O3structure type (space groupP3̄m1) in blue. Under high pressure, the tetragonal ThCr2Si2structure type (space groupI4/mmm) in red is more stable.


2018 ◽  
Vol 33 (1) ◽  
pp. 62-65
Author(s):  
Martin Etter

Commercially available trisodium hexachlororhodate (Na3RhCl6) was dehydrated and characterized by laboratory X-ray powder diffraction. The crystal structure is isostructural to the Na3CrCl6 structure type with space group P$\bar 31$c. Unit-cell parameters are a = 6.8116(1) Å, c = 11.9196(2) Å, V = 478.95(2) Å3, and Z = 2.


1999 ◽  
Vol 14 (1) ◽  
pp. 36-41 ◽  
Author(s):  
A. Meden ◽  
D. Kolar ◽  
S. Škapin

The structure type of La2Ti10.27Ga9.63O38 was revealed by a search-match using the PDF. A successful Rietveld refinement (Rp=8.9, Rwp=13.3, RB=4.20) confirmed the structure to be rhombohedral (space group R3¯, No. 148) with the refined unit cell parameters a=9.1878(1) Å, α=68.458(1)°, and V=646.374(1) Å3. The structure is compared to other compounds of the davidite type, and the observed and calculated powder data are given.


2014 ◽  
Vol 69 (3) ◽  
pp. 369-372
Author(s):  
Mariya Dzevenko ◽  
Inna Bigun

The new ternary silicide ErCo3Si2 adopts the ErRh3Si2 structure type (space group Imma, Pearson code oI24, Z = 4, a = 6:950(1), b = 9:020(2), c = 5:230(1) Å, R1 = 0:0565, wR2 = 0:0355, 253 F2 values, 23 variables). It is a deformation derivative of the CeCo3B2 structure type. The coordination of the Er atom shows a normal 20- vertex polyhedron [Er(Si6Co12Er2)]. The two similar coordination polyhedra of Co are a distorted icosahedron [Co(Si4Co4Er4)], and a distorted icosahedron with one capped face [Co(Si4Co5Er4)]. The Si atom is surrounded by the polyhedron [Si(Co6Si2Er3)]


2008 ◽  
Vol 23 (1) ◽  
pp. 60-62 ◽  
Author(s):  
Lingmin Zeng ◽  
Jiejun He ◽  
Pingli Qin ◽  
Xiangzhong Wei

A new ternary compound Al0.35GdGe2 has been synthesized and studied by means of X-ray powder diffraction technique. The ternary compound Al0.35GdGe2 crystallizes in the orthorhombicwith the CeNiSi2 structure type (space group Cmcm, a=4.0874(2) Å, b=16.1499(5) Å,c=3.9372(1) Å, Z=4, and Dcalc=8.007 g/cm3).


2005 ◽  
Vol 60 (9) ◽  
pp. 929-932 ◽  
Author(s):  
Roman V. Gumeniuk ◽  
Lev G. Akselrud ◽  
Yurij B. Kuz’ma

New compounds Ln5(Ag, Ga)19−x (Ln = Gd, Tb) have been found to crystallise with the Rb5Hg19 structure type (space group I4/m). The crystal structures were refined for Gd5Ag1.8Ga15 and Tb5Ag2Ga15.6 from X-ray powder data: a = 9.4635(1), c = 9.8638(2) Å , RI = 0.093 and a = 9.4313(1), c = 9.8491(2) Å , RI = 0.085, respectively. Some positions in the crystal structures of new the compounds are occupied partially.


Author(s):  
G. F. Claringbull ◽  
Max H. Hey ◽  
C. J. Payne

SummaryA singly terminated transparent, deep-garnet-red crystal originally weighing 1·7g. from a gem gravel from Mogok, Burma, proves to be a new mineral having Al2O3 76·2, SiO2 5·6, B2O3 2·2, CaO 15·7, H2O 0·7, Fe2O3 and MnO traces, total 100·4. Sp. gr. 4·01; ω 1·8159, ɛ 1·7875; H 8. The hexagonal unit cell has a 8·725, c 8·46 Å., space group P63, P63/m or P63 22, and contains approximately 38 O. The name painite is proposed in honour of A. C. D. Pain who recognized the unusual nature of the crystal.


Inorganics ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 57 ◽  
Author(s):  
Jakob B. Grinderslev ◽  
Mads B. Amdisen ◽  
Torben R. Jensen

Ammine metal borohydrides show large compositional and structural diversity, and have been proposed as candidates for solid-state ammonia and hydrogen storage as well as fast cationic conductors. Here, we report the synthesis method of ammine barium borohydrides, Ba(BH4)2·xNH3 (x = 1, 2). The two new compounds were investigated with time-resolved temperature-varied in situ synchrotron radiation powder X-ray diffraction, thermal analysis, infrared spectroscopy and photographic analysis. The compound Ba(BH4)2·2NH3 crystallizes in an orthorhombic unit cell with space group symmetry Pnc2, and is isostructural to Sr(BH4)2·2NH3, forming octahedral [Ba(NH3)2(BH4)4] complexes, which are connected into a two-dimensional layered structure, where the layers are interconnected by dihydrogen bonds, N–Hδ+⋯−δH–B. A new structure type is observed for Ba(BH4)2·NH3, which crystallizes in an orthorhombic unit cell with space group symmetry P212121, forming a three-dimensional framework structure of [Ba(NH3)(BH4)6] complexes. The structure is built from distorted hexagonal chains, where NH3 groups form dihydrogen bonds to the nearby BH4−-groups within the chain. Ba(BH4)2·2NH3 is unstable at room temperature and releases NH3 in two subsequent endothermic reactions with maxima at 49 and 117 °C, eventually reforming Ba(BH4)2. We demonstrate that the thermal stability and composition of the gas release for the ammine alkaline earth metal borohydrides can be correlated to the charge density of the metal cation, but are also influenced by other effects.


Sign in / Sign up

Export Citation Format

Share Document