New NMR Methods that Probe the Structure of Glasses

1990 ◽  
Vol 215 ◽  
Author(s):  
Robert Tycko ◽  
Gary Dabbagh
Keyword(s):  
Crystal Structures ◽  
Short Range ◽  
Two Dimensional ◽  
Structure Of Glasses ◽  
Orientational Ordering ◽  
Nmr Methods

AbstractTwo-dimensional NMR methods allow a determination of the relative orientations of nearby molecules in polycrystalline and noncrystalline solids. We describe these methods and present applications to the determination of the crystal structures of two forms of polycrystalline methanol and to the investigation of short range molecular orientational ordering in methanol glass and in atactic PMMA.

scholarly journals Mercury Cyanamide / Carbodiimide Networks: Synthesis and Crystal Structures of Hg2(NCN)Cl2 and Hg3(NCN)2Cl2

2002 ◽  
Vol 57 (10) ◽  
pp. 1108-1114 ◽  
Author(s):  
Xiaohui Liu ◽  
Richard Dronskowski
Keyword(s):  
Crystal Structure ◽  
Crystal Structures ◽  
Structure Determination ◽  
Crystal Structure Determination ◽  
Two Dimensional ◽  
Synthesis And Crystal Structure ◽  
Packing Efficiency ◽  
Inorganic Network

AbstractWe report about the synthesis and crystal structure determination of Hg2(NCN)Cl2 (P21/c (No. 14), Z = 4, a = 806.7(1), b = 907.1(2), c = 788.0(1) pm, β = 106.446(3)°, 1374 independent reflections, 67 variables, R1 = 0.0463) and Hg3(NCN)2Cl2 (Pca21 (No. 29), Z = 4, a = 702.0(2), b = 1078.5(2), c = 1050.3(2) pm, 1977 independent reflections, 71 variables, R1 = 0.0380). Both compounds contain infinite -Hg-NCN-Hg- zigzag chains which are linked by additional Hg atoms to result in two-dimensional frameworks characterized by 20-membered rings sharing edges. The remarkably flexible structural backbone [Hg3(NCN)2]2+ hosts additional Cl! anions and HgCl2 molecules in Hg2(NCN)Cl2 but only Cl- anions in Hg3(NCN)2Cl2, by that reaching a high packing efficiency in both cases.While Hg2(NCN)Cl2 exclusively contains carbodiimide N=C=N2- species, Hg3(NCN)2Cl2 is the first structural example of an inorganic network built up from both carbodiimide N=C=N2- and cyanamide N-C≡N2- groups.

Structural determination of oligosaccharides derived from lipooligosaccharide of Neisseria gonorrhoeae F62 by chemical, enzymic, and two-dimensional NMR methods

Biochemistry ◽  
1991 ◽  
Vol 30 (43) ◽  
pp. 10566-10575 ◽  
Author(s):  
Ryohei Yamasaki ◽  
Bradley E. Bacon ◽  
Wade Nasholds ◽  
Herman Schneider ◽  
J. M. Griffiss
Keyword(s):  
Neisseria Gonorrhoeae ◽  
Structural Determination ◽  
Two Dimensional ◽  
Nmr Methods

A NEUTRON DIFFRACTION DETERMINATION OF SHORT RANGE ORDER IN A Ni63.7Zr36.3 GLASS

1985 ◽  
Vol 46 (C8) ◽  
pp. C8-87-C8-92 ◽  
Author(s):  
R. Bellissent ◽  
J. Bigot ◽  
Y. Calvayrac ◽  
S. Lefebvre ◽  
A. Quivy
Keyword(s):  
Neutron Diffraction ◽  
Short Range ◽  
Short Range Order ◽  
Range Order ◽  
Diffraction Determination
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