X-ray single crystal study of reversible thermochromism and the pecularities of atomic thermal motion in n, n-diphenylguanidinium(1+) hexabromotellurate (IV)

2005 ◽  
Vol 46 (4) ◽  
pp. 672-682 ◽  
Author(s):  
B. V. Bukvetskii ◽  
A. G. Mirochnik
2002 ◽  
Vol 58 (2) ◽  
pp. 191-197 ◽  
Author(s):  
O. Perez ◽  
A. C. Masset ◽  
H. Leligny ◽  
G. Baldinozzi ◽  
D. Pelloquin ◽  
...  

The structure of the m = 2 tubular compound Bi4Sr12Co8O30−δ, bismuth strontium cobalt oxide, was determined by single-crystal X-ray diffraction. This phase of orthorhombic symmetry exhibits a very strong tetragonal pseudosymmetry. The structure consists of 90°-oriented Bi2Sr2CoO6+δ slices, four Co atoms wide, forming [Sr4Co4O13]∞ pillars at their intersection. The Co atoms in these pillars form four corner-sharing CoO5 bipyramids. In the resulting [Co4O13] cluster, an anionic disorder is evidenced and discussed. Then, an accurate description of the particular structure of the pillars is given. Finally, a comparison with the Mn tubular compound Bi3.6Sr12.4Mn8O30−δ is carried out.


2000 ◽  
Vol 85 (9) ◽  
pp. 1164-1171 ◽  
Author(s):  
Giovanni B. Andreozzi ◽  
Francesco Princivalle ◽  
Henrik Skogby ◽  
Antonio Della Giusta

1978 ◽  
Vol 31 (2) ◽  
pp. 415 ◽  
Author(s):  
CL Raston ◽  
AH White ◽  
AC Willis

The crystal structure of the title compound, [Ni(en)3] (ClO4)2,H2O, has been determined from single-crystal X-ray diffraction data at 295(1) K and refined by least squares to a residual of 0.093 for 1400 'observed' reflections. Crystals are orthorhombic, P bca, a 17.043(7), b 15.922(6), c 13.496(5) Ǻ, Z 8. The precision of the structure determination is adversely affected by very high perchlorate thermal motion. <Ni-N> is 2.13 Ǻ.


2002 ◽  
Vol 14 (5) ◽  
pp. 929-934 ◽  
Author(s):  
Luca Bindi ◽  
Oleg G. Safonov ◽  
Yuriy A. Litvin ◽  
Leonid L. Perchuk ◽  
Silvio Menchetti

1999 ◽  
Vol 18 (8) ◽  
pp. 1019-1032 ◽  
Author(s):  
Mohamed Selkti ◽  
Rima Kassab ◽  
Hélène Parrot Lopez ◽  
Françoise Villain ◽  
Colette de Rango

2006 ◽  
Vol 61 (1) ◽  
pp. 23-28 ◽  
Author(s):  
Vasyl’ I. Zaremba ◽  
Yaroslav M. Kalychak ◽  
Mariya V. Dzevenko ◽  
Ute Ch. Rodewald ◽  
Birgit Heying ◽  
...  

The rare earth-cobalt-indides RE14Co3In3 (RE = Y, Tb, Dy, Ho, Er) were prepared in polycrystalline form from the elements by arc-melting. Small single crystals were grown through a special annealing sequence. The compounds were investigated on the basis of X-ray powder and single crystal data: Lu14Co2In3 (Gd14Co3In2.7) type, P42/nmc, Z = 4, a = 959.0(1), c = 2319.1(5) pm, wR2 = 0.055, 2289 F2 values, 65 variables for Y13.90Co2.99In3.02, a = 953.8(1), c = 2315.8(5) pm, wR2 = 0.108, 2357 F2 values, 65 variables for Tb13.92Co3.01In2.92, a = 949.24(3), c=2296.5(1) pm, wR2= 0.129, 2518 F2 values, 65 variables for Dy13.90Co2.97In2.95, a=946.3(1), c = 2289.0(5) pm, wR2 = 0.099, 2297 F2 values, 64 variables for Ho14Co2.80In2.89, and a = 941.0(1), c = 2274.2(5) pm, wR2 = 0.140, 2450 F2 values, 65 variables for Er13.83Co2.88In3.10. All RE14Co3In3 indides show a small degree of In/Co mixing (between 7 and 16% Co) on the 4c In1 site and defects on the 8g Co1 positions (between 84 and 95% Co). Except for the holmium compound, the RE14Co3In3 intermetallics also reveal RE/In mixing on the 4c RE1 sites, leading to the refined compositions. The seven crystallographically independent RE sites have between 9 and 10 nearest RE neighbors. The RE14Co3In3 structures consist of a complex intergrowth of rare earth based polyhedra. Both cobalt sites have a distorted trigonal-prismatic rare earth coordination. An interesting feature is the In2-In2 dumb-bell with an In2-In2 distance of 300 pm (for Ho14Co2.80In2.89). The crystal chemistry of the RE14Co3In3 indides is discussed.


1982 ◽  
Vol 38 (7) ◽  
pp. 1966-1972 ◽  
Author(s):  
J. S. W. Overell ◽  
G. S. Pawley

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