Structure determination of sodium nitrate near the order-disorder phase transition

1984 ◽  
Vol 45 (8) ◽  
pp. 1317-1327 ◽  
Author(s):  
J. Lefebvre ◽  
R. Fouret ◽  
C.M.E. Zeyen
Keyword(s):  
Phase Transition ◽  
Sodium Nitrate ◽  
Structure Determination ◽  
Disorder Phase Transition

Crystal Structure Determination of the Nonclassical 2-Norbornyl Cation

Science ◽  
2013 ◽  
Vol 341 (6141) ◽  
pp. 62-64 ◽  
Author(s):  
F. Scholz ◽  
D. Himmel ◽  
F. W. Heinemann ◽  
P. v. R. Schleyer ◽  
K. Meyer ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
Data Collection ◽  
Quantum Chemical ◽  
Molecular Structures ◽  
X Ray ◽  
Disorder Phase Transition ◽  
Carbonium Ion ◽  
Phase Data

After decades of vituperative debate over the classical or nonclassical structure of the 2-norbornyl cation, the long-sought x-ray crystallographic proof of the bridged, nonclassical geometry of this prototype carbonium ion in the solvated [C7H11]+[Al2Br7]–• CH2Br2salt has finally been realized. This achievement required exceptional treatment. Crystals obtained by reacting norbornyl bromide with aluminum tribromide in CH2Br2undergo a reversible order-disorder phase transition at 86 kelvin due to internal 6,1,2-hydride shifts of the 2-norbornyl cation moiety. Cooling with careful annealing gave a suitably ordered phase. Data collection at 40 kelvin and refinement revealed similar molecular structures of three independent 2-norbornyl cations in the unit cell. All three structures agree very well with quantum chemical calculations at the MP2(FC)/def2-QZVPP level of theory.

A Central Peak in the Order-Disorder Phase Transition of Sodium Nitrate

1985 ◽  
Vol 54 (10) ◽  
pp. 3697-3700 ◽  
Author(s):  
Hiroshi Yasaka ◽  
Akira Sakai ◽  
Toshirou Yagi
Keyword(s):  
Phase Transition ◽  
Sodium Nitrate ◽  
Central Peak ◽  
Disorder Phase Transition

ORDER-DISORDER PHASE TRANSITION OF Au(110)-(1x2) RECONSTRUCTION

1988 ◽  
Vol 49 (C6) ◽  
pp. C6-269-C6-273 ◽  
Author(s):  
H. Q. NGUYEN ◽  
Y. KUK ◽  
P. J. SILVERMAN
Keyword(s):  
Phase Transition ◽  
Disorder Phase Transition

Ab initio structure determination of cytochrome c6 by combined reciprocal space-real space approach

2003 ◽  
Vol 218 (1) ◽  
Author(s):  
K. Chowdhury ◽  
S. Ghosh ◽  
M. Mukherjee
Keyword(s):  
Cytochrome C ◽  
Ab Initio ◽  
Structure Determination ◽  
Direct Method ◽  
Real Space ◽  
Reciprocal Space ◽  
Cytochrome C6 ◽  
Ab Initio Structure ◽  
Space Approach

AbstractThe direct method program SAYTAN has been applied successfully to redetermine the structure of cytochrome c

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