Biomolecule Recognition Using Transition Metal Ions and Hydrogen Bonding

Author(s):  
A.J. Plaunt ◽  
M. de Lourdes Betancourt-Mendiola ◽  
B.D. Smith
2002 ◽  
Vol 124 (18) ◽  
pp. 5197-5205 ◽  
Author(s):  
Cédric Desplanches ◽  
Eliseo Ruiz ◽  
Antonio Rodríguez-Fortea ◽  
Santiago Alvarez

2019 ◽  
Vol 8 (2S11) ◽  
pp. 3182-3190

Chemical speciation of ternary complexes of L-arginine and L-aspartic acid with essential transition metal ions was studied pH metrically. The following MLX, MLXH and ML2X ternary species are detected and reported in this paper. The existence of different ternary species is established from modeling studies using the computer program MINIQUAD75. The relative concentrations (M: L: X=1:2:2, 1:2:4, 1:4:2) and stabilities of the ternary species are compared with those of binary species. The extra stability associated with the ternary complexes is attributed to factors such as charge neutralization, chelate effect, stacking interactions and hydrogen bonding. Trend in variation of stability constants with the change in the mole fraction of the surfactant in various micellar media is explained on the basis of electrostatic and non-electrostatic forces. Distribution diagrams in relation to pH and plausible structures were presented.


RSC Advances ◽  
2014 ◽  
Vol 4 (56) ◽  
pp. 29702-29714 ◽  
Author(s):  
Yan Li ◽  
Yiming Jia ◽  
Zhenwen Wang ◽  
Xianghui Li ◽  
Wen Feng ◽  
...  

Disruption of intramolecular H-bonding via N-substitution leads to rotational isomerization and much improvement in extraction of Hg2+.


2008 ◽  
Vol 12 (12) ◽  
pp. 1242-1249 ◽  
Author(s):  
Martin Bröring

This account summarizes recent advances in the coordination chemistry of tripyrrins and related ligands with a special emphasis on the structural chemistry of coordination polymers with such ligands. The tripyrrin ligand is unique in supporting the formation of 1D- and 3D-supramolecular structures from pentacoordinate transition metal ions due to an effective blockage of their sixth coordination site. Linear coordination polymers have been observed with a multitude of bidentate and tridentate bridging ligands like trifluoroacetate, azide, thio- and selenocyanate, and higher order pseudohalides. Homo- and heterodimetallic species have been obtained by the use of cyanometallates and could be characterized structurally in two cases. Besides the covalent coordination bonds, several secondary interactions like hydrogen bonding and π-stacking were found to support these coordination polymers and are demonstrated to allow the preparation of species with functionalized inner surfaces.


Author(s):  
R. Ai ◽  
H.-J. Fan ◽  
L. D. Marks

It has been known for a long time that electron irradiation induces damage in maximal valence transition metal oxides such as TiO2, V2O5, and WO3, of which transition metal ions have an empty d-shell. This type of damage is excited by electronic transition and can be explained by the Knoteck-Feibelman mechanism (K-F mechanism). Although the K-F mechanism predicts that no damage should occur in transition metal oxides of which the transition metal ions have a partially filled d-shell, namely submaximal valence transition metal oxides, our recent study on ReO3 shows that submaximal valence transition metal oxides undergo damage during electron irradiation.ReO3 has a nearly cubic structure and contains a single unit in its cell: a = 3.73 Å, and α = 89°34'. TEM specimens were prepared by depositing dry powders onto a holey carbon film supported on a copper grid. Specimens were examined in Hitachi H-9000 and UHV H-9000 electron microscopes both operated at 300 keV accelerating voltage. The electron beam flux was maintained at about 10 A/cm2 during the observation.


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