(μ-Di-hydrogen pyrazine-2,3,5,6-tetra-carboxyl-ato-κ(6) O (2),N (1),O (6);O (3),N (4),O (5))bis-(di-aqua-lithium)
Wojciech Starosta1, Janusz Leciejewicz1
1Institute of Nuclear Chemistry and Technology, ul.Dorodna 16, 03-195 Warszawa, Poland.
Abstract:
The structure of the title compound, [Li2(C8H2N2O8)(H2O)4]·H2O, is composed of dinuclear mol-ecules in which the ligand bridges two symmetry-related Li(I) ions, each coordinated also by two water O atoms, in an O,N,O'-manner. The Li and N atoms occupy special positions on twofold rotation axes, whereas a crystal water mol-ecule is located at the inter-section of three twofold rotation axes. The Li(I) cation shows a distorted trigonal-bipyramidal coordination. Two carboxyl-ate groups remain protonated and form short inter-ligand hydrogen bonds. The mol-ecules are held together by a network of hydrogen bonds in which the coordinating and solvation water mol-ecules act as donors and carboxyl-ate O atoms as acceptors, forming a three-dimensional architecture.
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